The latest on the Ukraine-Russia border crisis

As world leaders scramble to find a diplomatic solution over the ongoing Russia-Ukraine tensions, talk has turned to the 2015 Minsk Agreement as a possible way out of the crisis.

The agreement, the second of its kind (and the one that matters), was hammered out in the Belarusian capital in a bid to end what was then a bloody 10-month conflict in eastern Ukraine.

But Minsk II has never been fully implemented, with its key issues still unresolved.

Here's what you need to know:

Who are the key players? A rare meeting between Russian, Ukrainian, German and French leaders in February 2015 sought to bring peace to areas of Ukraine that had been taken over by pro-Russian separatists the year before. Those areas, in Ukraine's Donbas region, became known as the Luhansk People's Republic (LPR) and the Donetsk People's Republic (DPR). The Ukrainian government in Kyiv asserted the two regions were in effect Russian-occupied.

The talks also aimed to work towards a political settlement for the region.

The result, Minsk II, was signed by representatives of Russia, Ukraine, the separatist leaders and the Organization for Security and Co-operation in Europe (OSCE). It was subsequently endorsed by a UN Security Council resolution.

What were the conditions of the agreement? A ceasefire. In February 2015, there was still heavy fighting in some areas between Ukrainian forces and Russian-supported rebels, with the Ukrainians taking heavy losses.

The withdrawal of heavy weaponry from the frontlines.

That the OSCE — a 57-member security organization that also includes the US and Canada — monitor the frontlines.

A dialogue on local elections in areas occupied by pro-Russian rebels.

The restoration of full economic and social links between the two sides, so that, for example, pensions could be paid.

That Ukrainian government control be restored over the border with Russia.

The withdrawal of all foreign forces and mercenaries.

Constitutional reform that would provide some autonomy to the regions of Ukraine's eastern Donbas region no longer under the central government's control.

Read the full story here.

British Foreign Secretary Liz Truss said on Thursday that despite Russia’s claims, its military buildup around Ukraine “shows no signs of slowing down.” 

“There is currently no evidence that forces are withdrawing. Russia must step back from the brink. The Kremlin has had every offer of diplomacy… Time after time, they have chosen not to engage with these proposals but to obfuscate and object,” Truss said in Kyiv following a meeting with her Ukrainian counterpart Dmytro Kuleba.  

“Russia thinks that NATO should not expand; the truth is that countries want to join NATO. People want insurance and they see safety in numbers, and this is only accelerated by Russia’s belligerence,” the foreign secretary added.  

She went on to say that even if Russia pulls back from its border with Ukraine, the “problem will not have gone away. The free world needs to draw a line under a decade of drift.” 

Truss said she was surprised by seeing “China’s leaders aligning themselves with the Kremlin” as Beijing claims "a policy of non-interference.”  

“If China wants to be seen as a responsible global actor, they should be doing everything possible to ensure that Russia steps back,” she added.  

Truss blamed Russia for “violating its commitments, and probing our weaknesses” for years and urged the West to “wise up.”  

“In dangerous times, we have to take a hard-headed approach. That includes being ready to accept short-term pain for long-term gain, whether through imposing tough sanctions, for cutting strategic dependence by opposing Nord Stream 2,” she added.  

British Prime Minister Boris Johnson on Thursday accused Russia of fabricating a pretext to invade Ukraine by attacking a kindergarten in Donbas. 

According to the Ukrainian armed forces, in a shelling by “Russian occupation troops” on the settlement of Stanytsia Luhanska, the kindergarten in the Ukrainian-controlled territory was hit by Thursday.  

Video and images confirmed by CNN show that it was hit by a shell in the attack on the community.

While Johnson told reporters the attack was a “false flag operation designed to discredit the Ukrainians, designed to create a pretext, a spurious provocation for Russian action,” this particular incident should not be conclusively termed a false flag operation by Russia intended to blame Ukraine for an attack on its own community.  

However, world leaders including US President Biden, have accused Russia of carrying out “false flag” operations in recent days designed to blunt the impact of any pretext Russia may use to invade Ukraine.  

Ukrainian armed forces and separatists controlling parts of eastern Ukraine have said there has been renewed shelling in the Donbas region, with Ukrainian President Volodymyr Zelensky calling the kindergarten shelling "a big provocation." 

“We fear very much that that is the kind of thing we'll see more of over the next few days,” Johnson warned, adding that if Russia was “so mad as to invade,” it would result in a bloody and protracted conflict.” 

Johnson reiterated that that the UK will apply heavy economic sanctions on Russia should it invade Ukraine, but continued: “I do think there is still time for the Putin regime to step back.”

“If Russia was so mad as to invade, I don't think people should imagine that this will be a brief business. This will be a bloody and protracted conflict in which I'm afraid that there will be many casualties, including many Russian casualties and I just hope that people in Russia can see that for what it is,” Johnson said.

US Secretary of State Antony Blinken said he proposed meeting with Russian Foreign Minister Sergey Lavrov in Europe next week in a letter to continue the diplomatic path to resolving the crisis created by Russia massing troops near Ukraine’s borders, as well as meetings of the NATO-Russia Council and the Organization for Security and Cooperation in Europe.

Blinken said these meetings present “every opportunity” for Russia to demonstrate its commitment to a diplomatic resolution.

US Secretary of State Antony Blinken said he was speaking to the United Nations about Russia and Ukraine "not to start a war, but to prevent one."

He urged Russia to use diplomacy as a solution to the crisis.

"And Russia isn't only hearing from us. The international chorus has grown louder and louder," the US official said. "If Russia doesn't invade Ukraine, then we will be relieved that Russia changed course and proved our predictions wrong. That would be a far better outcome than the course we're currently on, and we'll gladly accept any criticism that anyone directs at us."

Blinken said he sent a letter to Russian Foreign Minister Sergey Lavrov proposing they meet next week in Europe. He is also proposing meetings of the NATO-Russia Council and the Organization for Security and Co-operation in Europe.

"These meetings can pave the way for a summit of key leaders in the context of deescalation to reach understandings on our mutual security concerns. As lead diplomats for our nations, we have a responsibility to make every effort for diplomacy to succeed, to leave no diplomatic stone unturned," he said.

He said Russia will likely respond with dismissals that the US is "stoking hysteria."

"The Russian government can announce today with no qualifications, equivocation or deflection that Russia will not invade Ukraine, stated clearly, stated plainly to the world — and then demonstrate it by sending your troops, your tanks, your planes, back to hangars and sending diplomats to the negotiating table. In the coming days, the world will remember that commitment. Or the refusal to make it," he concluded.

US Secretary of State Antony Blinken addressed misinformation that he said Russia continues to spread as it targets Ukraine and possible ways Moscow may attack, saying he hoped to “influence Russia to abandon the path of war and choose a different path while there's still time.”

"We don't know precisely how things will play out. But here's what the world can expect to see unfold," Blinken said.

"First, Russia plans to manufacture a pretext for its attack. ... We don't know exactly the form it will take. It could be a fabricated so-called terrorist bombing inside Russia. The invented discovery of the mass grave, a staged drone strike against civilians or a fake, even a real attack using chemical weapons," he said.

Then, he said, "the highest levels of the Russian government may theatrically convene crisis and Russia must respond to defend citizens or ethnic Russians in Ukraine."

There may be conventional attacks, or they could take the form of cyberattacks and could target specific groups of Ukrainians, he said.

He also warned that Russia is planning to “target specific groups of Ukrainians.”

CNN's Michael Conte, Jennifer Hansler and Christin Sierra contributed reporting to this post.

US Secretary of State Antony Blinken called the Ukraine-Russia crisis a "moment of peril" while addressing the United Nations Security Council in New York Thursday.

"We must address what Russia is doing right now to Ukraine," he said.

Blinken said that intelligence clearly indicates that the buildup of Russian forces signals an attack against Ukraine in "the coming days."

Secretary of State Antony Blinken is addressing the United Nations Security Council as Ukraine-Russia tensions continue to unfold and the US warns an invasion could be near.

"Every indication that we have is that they are prepared to go into Ukraine, attack Ukraine," President Biden told reporters as he left the White House on Thursday.

Russia expelled the second-most senior diplomat at the US embassy in Moscow without any justification Thursday, in what the Biden administration views as an escalatory move, the State Department said.

US Ambassador to the UN Linda Thomas-Greenfield said Blinken was addressing the UN because "this is a crucial moment."

Meanwhile, US Secretary of Defense Lloyd Austin today also said the US government is not seeing any kind of withdrawal of Russian troops from Ukraine's border, instead seeing Russia adding to its capabilities and troops "even in the last couple of days."

During a press conference at NATO headquarters in Brussels, Austin said the US is seeing Russia move some troops closer to the border, "fly in more combat and support aircraft," "sharpen their readiness in the Black Sea" and even "stocking up their blood supplies.

Russia expelled the second-most senior diplomat at the US embassy in Moscow without any justification in what the Biden administration views as an "escalatory" move, the State Department said on Thursday. 

Gorman departed Moscow last week, according to a senior State Department official, and returned to the US. He was expelled by Moscow earlier this year and was given two weeks to depart.

The US is considering its response.

This diplomatic issue comes to the fore amid growing concerns about a Russian invasion of Ukraine.

More background: Russia has continually forced the US to reduce the size of its diplomatic footprint in the country in recent years. Gorman’s tour in Russia had not ended, he had a valid visa, and he had been in Russia less than three years, the spokesperson added. 

“We call on Russia to end its baseless expulsions of U.S. diplomats and staff and to work productively to rebuild our missions. Now more than ever, it is critical that our countries have the necessary diplomatic personnel in place to facilitate communication between our governments,” the spokesperson said.