An arms-control group is pressuring President-elect Donald Trump Donald John TrumpBiden on Trump's refusal to commit to peaceful transfer of power: 'What country are we in?' Romney: 'Unthinkable and unacceptable' to not commit to peaceful transition of power Two Louisville police officers shot amid Breonna Taylor grand jury protests MORE to repudiate comments he reportedly made claiming he’s fine with a nuclear arms race.

The Center for Arms Control and Non-Proliferation, which on Thursday expressed alarm at Trump’s tweet calling for the United States to strengthen and expand its nuclear arsenal, on Friday released a trio of statements calling on Trump to disavow his comments.

“Any nuclear escalation, let alone a new nuclear arms race, is dangerous, destabilizing and places the entire planet further at risk,” John Tierney, the center’s executive director, said in a statement.

ADVERTISEMENT

“This form of nuclear saber rattling could represent the most dangerous turn in global nuclear weapons policy since the end of the Cold War. Mr. Trump must immediately disavow his own statement for the sake of U.S. and international security.”

On Thursday, Trump tweeted that “the United States must greatly strengthen and expand its nuclear capability until such time as the world comes to its senses regarding nukes.”

Aides have since sought to downplay the tweet, but Trump reportedly doubled down in off-camera comments to MSNBC host Mika Brzezinski.

Brzezinski said on Friday morning’s “Morning Joe” that Trump told her: “Let it be an arms race, we will outmatch them at every pass ... and outlast them all.”

In response, Tierney said there’s been decades of bipartisan consensus on reducing nuclear weapons that Trump’s plan would reverse.

“The United States is already planning to spend approximately $1 trillion on its nuclear arsenal over the next three decades,” he added. “Mr. Trump will also have to explain how a new nuclear arms race would be affordable, let alone a sound policy choice. As the President-elect, every major statement he makes can have serious ramifications.”

Former Sen. Byron Dorgan (D-N.D.), a member of the center’s national advisory board, said a nuclear arms race would put “everyone on this planet in greater danger.”

“The statements made by President-elect Trump undermine decades of work the United States and its allies have been involved in to reduce nuclear weapons stockpiles and to prevent the additional proliferation of nuclear weapons,” he added in a statement.

Jim Walsh, an international security expert at the Massachusetts Institute of Technology and a center contributor, added that Trump “clearly” does not understand the implications of his statements.

“He is not yet president, has no confirmed cabinet or security team in place and skips his intelligence briefings,” he said in a statement. “Using Twitter to blurt out ill-conceived changes to US nuclear weapons doctrine is unwise if not downright dangerous.”