Former President Jimmy Carter has added his voice to those urging President Donald Trump to refrain from launching an illegal military attack on Syria, warning of the serious dangers—including nuclear conflagration—that could result.

“I pray that he would keep our country at peace and not exaggerate or exacerbate the challenges that come up with North Korea, in Russia, or in Syria,” Carter told The Associated Press about Trump’s recent threats.

“I hope he realizes very profoundly as I did, and as other presidents have done,” Carter continued, “that any nuclear exchange could involve catastrophe for all human beings.”

Carter pointed out that even a military attack that doesn’t escalate into a nuclear exchange “is a dangerous thing” that can unleash unpredictable consequences.

Anti-war activists are also pressuring Trump to proceed cautiously.

“There is no proof yet of a Syrian government gas attack,” noted Veterans for Peace President Gerry Condon. “Even if the reports are true, a military response will only lead to more death and destruction, and dangerous escalations.”

Condon also pointed to nuclear concerns—considering Russia’s support for Syrian President Bashar al-Assad.

“We are talking about a direct confrontation between the two nuclear superpowers,” Condon said. “Why would the U.S. risk nuclear war over dubious chemical weapons claims?”

Pleas for restraint from peace advocates, members of Congress, international law experts, and at least one former president come amid mixed messages from Trump and an alarming report by Russia’s state-owned television station about possible war with the United States. 

In a news segment on Wednesday, as Common Dreams reported, one Russian anchor “explained to viewers how to prepare for a potential war by stocking a bomb shelter—while images of nuclear explosions were shown behind him.”