CNN  — 

Democratic Sen. Bob Menendez of New Jersey remained defiant on Monday after being indicted on bribery charges at the end of last week, saying he believes he will be exonerated as he responded to some of the specific charges and evidence outlined by prosecutors.

Menendez’s comments come amid a flurry of calls for his resignation – including from his own party and from his Senate colleagues. On Monday, Sens. Sherrod Brown of Ohio and Peter Welch of Vermont became the latest Democrats in the chamber call on Menendez to step down, joining Pennsylvania Sen. John Fetterman.

In a statement delivered to reporters, Menendez offered some of his first public defense against some of the evidence discovered by investigators during their search of his home, including hundreds of thousands of dollars in cash, which he argued he had on hand for emergencies and described as an “old-fashioned” habit derived from his family’s experience in Cuba.

“For 30 years, I have withdrawn thousands of dollars in cash from my personal savings account, which I have kept for emergencies, and because of the history of my family facing confiscation in Cuba,” said Menendez. “Now this may seem old fashioned, but these were monies drawn from my personal savings account based on the income that I have lawfully derived over those 30 years.”

According to the indictment, searches of Menendez’s home and safe deposit box that federal agents conducted in 2022 turned up nearly $500,000 in cash, including in envelopes inside jackets emblazoned with Menendez’s name. Prosecutors say some of the envelopes had the fingerprints or DNA of one of the business contacts from whom the senator is accused of taking bribes.

Menendez has been charged with three alleged crimes, including being on the receiving end of a bribery conspiracy. The conspiracy counts also charge his wife and three people described as New Jersey associates and businessmen.

The group is accused of coordinating to use Menendez’s power as a US senator to benefit them personally and to benefit Egypt.

On Monday, Menendez defended his record as it relates to Egypt, saying, “If you look at my actions related to Egypt during the period described in this indictment, and throughout my whole career, my record is clear and consistent in holding Egypt accountable for its unjust detention of American citizens and others, its human rights abuses, its deepening relationship with Russia, and efforts that have eroded the independence of the nation’s judiciary, among a myriad of concerns.”

Democratic Sen. Robert Menendez of New Jeresey speaks in Union City on September 25, 2023.

Menendez has been called upon to resign by a growing list of prominent Democrats – including the New Jersey governor and six members of the state’s congressional delegation. Rep. Andy Kim announced Saturday plans to challenge Menendez in the Democratic primary next year should Menendez run again for his US Senate seat.

And on Monday, Brown and Welch joined Fetterman to become the second and third Senate Democrats to call for Menendez to step down.

“Senator Menendez has broken the public trust and should resign from the U.S. Senate,” said Brown, who is running for reelection next year.

Welch said in a statement later in the day that “the shocking and specific allegations against Senator Menendez have wholly compromised his capacity to be that effective Senator,” adding: “I encourage Senator Menendez to resign.”

Fetterman, who first called for Menendez’s resignation over the weekend, will return $5,000 in donations his campaign received from Menendez’s political action committee, according to the Pennsylvania Democrat’s office.

The New Jersey senator has denied wrongdoing and pushed back on calls to resign.

On Monday, Menendez accused those who “rushed to judgment” of doing so for “political expediency.”

“I recognize this will be the biggest fight yet,” Menendez said, referencing the legal battle ahead. “But as I have stated throughout this whole process, I firmly believe that when all the facts are presented, not only will I be exonerated, but I still will be New Jersey’s senior senator.”

This story has been updated with additional developments.

CNN’s Manu Raju contributed to this report.