Former Vice President Joe Biden harshly criticized President Donald Trump for his tweets threatening to hit Iranian sites if there was any retaliation for the killing of top Iranian Gen. Qassem Soleimani. “When he makes statements like that, it just seems to me to be he’s going off on a tweetstorm on his own, and it’s incredibly dangerous and irresponsible,” Biden told reporters before a campaign event in Iowa. Biden said that Trump is becoming “more irrational” as “the walls close in.”

The more the walls close in on this guy, the more irrational he becomes. https://t.co/Nba7Color1 — Joe Biden (@JoeBiden) January 5, 2020

The former vice president, who is making a point of emphasizing his foreign policy expertise on the campaign trail since the killing of Soleimani, said that Trump’s words are particularly worrisome because it’s unclear what is going through his head or whether he has discussed anything with the country’s allies. “No president has a right to take our country to war without the informed consent of Americans—informed consent. And right now we have no idea what this guy has in mind, we have no idea,” Biden said. “He’s isolated us from our partners. He’s isolated us from our NATO allies.”

While on the campaign trail, Biden has talked about the Soleimani killing as an example of the high stakes on the world stage and why his qualifications make him the right man for the job. “This all just reinforces the stakes of this election in my view,” Biden said on Saturday. “With all due respect, I think I’m better prepared than of anybody running for president right now.”

The former vice president was hardly the only Democrat to criticize Trump for his threatening tweets. Fellow presidential hopeful Elizabeth Warren said Trump was “threatening to commit war crimes.” She also warned that Trump’s threats “put our troops and diplomats at greater risk.”

You are threatening to commit war crimes. We are not at war with Iran. The American people do not want a war with Iran. This is a democracy. You do not get to start a war with Iran, and your threats put our troops and diplomats at greater risk. Stop. pic.twitter.com/RoXRgb9GsK — Elizabeth Warren (@ewarren) January 5, 2020

Rep. Alexandria Ocasio-Cortez called the president a “monster” for the threats that imply innocent civilians could be killed. “This is a war crime,” Ocasio-Cortez wrote. “Threatening to target and kill innocent families, women and children—which is what you’re doing by targeting cultural sites—does not make you a ‘tough guy,’ It does not make you ‘strategic.’ It makes you a monster.”

Rep. Ilhan Omar, meanwhile, expressed shock that “the president of the United States is threatening to commit war crimes on Twitter.”

The President of the United States is threatening to commit war crimes on Twitter.



God help us all! #25thAmendment https://t.co/nYZSvpo8rG — Ilhan Omar (@IlhanMN) January 5, 2020