Sen. Bernie Sanders issued a sudden live video saying that war with Iran would be "many times worse than the Iraq War," in response to reporting by The New York Times saying that the Trump administration is reviewing a plan to send up to 120,000 troops to the Middle East.

The idea was reportedly spearheaded by John Bolton, the president's national security adviser, who served in the George W. Bush administration at the height of the conflict in Iraq.

"Sixteen years ago, the U.S. committed one of the worst blunders in history of our country by attacking Iraq," Sanders said in a video recorded live on Periscope and posted to Twitter. He called out Bolton as one of the "leading advocates" of the war, which he called the "biggest foreign policy disaster" in modern U.S. history.

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"Now, based on that disaster that he help bring about in Iraq, it appears that John Bolton wants a war in Iran," Sanders said. "A war in Iran would, in my view, be many times worse than the Iraq War."

The senator said that he was working to build a coalition in Congress to force President Trump to ask Congress for authorization if he wants to engage in military action in Iran. Congress authorized Mr. Bush to take action in Iraq in 2002, but did not formally declare war. Opponents of the war in Iraq argue that President Bush did not have the constitutional authority to essentially declare war in the country.

"I am working hard to see if we can get 51 members of the U.S. Senate, as well as a majority in the House of Representatives to make clear that before the President takes any military action in Iran or anyplace else, he must seek authorization from the Congress," Sanders said in the video. "Taking us into a war without congressional authorization would be unconstitutional and illegal."

Mr. Trump denied the Times' reporting on Tuesday morning, calling the paper "fake news."

"Now, would I do that? Absolutely," Mr. Trump told reporters. "But we have not planned for that. Hopefully, we are not going to have to plan for that. And if we did that, we'd send a hell of a lot more troops than that."