CNN  — 

Climate activist Greta Thunberg has joked that she is adopting a “net-zero” approach to cursing, an apparent response to criticism of her use of strong language at a demonstration earlier this week.

The 18-year-old Swede was filmed singing “You can shove your climate crisis up your a**e” to the tune of well-known children’s song “She’ll be coming ‘round the mountain,” alongside fellow climate campaigners on the first day of the COP26 summit in Glasgow, Scotland.

Greta Thunberg, surrounded by other climate protesters on Monday

Following a backlash by some over her choice in words, Thunberg posted a tongue-in-cheek response to her five million Twitter followers on Wednesday morning.

“I am pleased to announce that I’ve decided to go net-zero on swear words and bad language. In the event that I should say something inappropriate I pledge to compensate that by saying something nice. #COP26,” she wrote.

The teen activist has regularly repurposed terms and phrasing touted by world leaders as examples of progress on the climate crisis, and instead decried the rhetoric as empty words and unfulfilled promises.

Thunberg made a speech at the recent Youth for Climate conference in which she roasted leaders, suggesting their climate talk amounted to “blah, blah, blah.”

Scotland's First Minister, Nicola Sturgeon, center, talks with climate activists Vanessa Nakate, right, and Greta Thunberg, left, during the COP26 conference.

On Monday, Thunberg joined other “Fridays for Future” activists at a demonstration at Festival Park in Glasgow, near the UN climate summit, where she once again mocked politicians for their inaction on climate.

She said the politicians and delegates gathered at the COP talks were “pretending to take our future seriously.”

“Change is not going to come from inside there. That is not leadership, this is leadership,” Thunberg added, referring to the group of protesters assembled outside.

“This is what leadership looks like. We say no more blah blah blah, no more exploitation of people and nature and the planet… No more whatever the f**k they’re doing inside there,” she continued.

Over the weekend, the environmental campaigner received a rock star welcome when she was mobbed by supporters at Glasgow’s Central Station.

Thunberg gestures to cameras and supporters after arriving in Glasgow on Saturday ahead of the COP26 summit.

After traveling north from London by train, Thunberg appeared to be in good spirits, giving photographers a thumbs-up as she made her way through the station upon arrival, surrounded by police and fellow climate activists.