President Trump is doubling down to defend his decision to withdraw U.S. troops from Syria immediately in the face of intense and swift backlash from even some of his closest allies in Washington. And in doing so, the president appears to be contradicting both himself and publicly available information.

Mr. Trump declared ISIS "defeated" in Syria in a tweet Wednesday, a claim he reiterated in a video posted to Twitter Thursday. On Thursday morning, he started out his day tweeting quotes from the few public figures who praised his decision.

In a single tweet, the president made claims about ISIS in Syria that both appeared to contradict himself and claims made publicly by Russia. Mr. Trump claimed on Twitter that "Russia, Iran, Syria & many others are not happy about the U.S. leaving, despite what the fake News says, because now they will have to fight ISIS and others, who they hate, without us."

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But Russian President Vladimir Putin applauded the U.S. decision to leave, and the Russian Embassy in the U.S. also praised the decision. Aside from that, key foreign policy experts, including those on Capitol Hill and in the Trump administration, have warned that leaving Syria creates a vacuum for Russia and for Syrian dictator Bashar Al Assad.

"I do generally agree with the president of the United States," Putin told journalists Thursday, welcoming Mr. Trump's decision.

The president's claim that those nations now "will have to fight ISIS" also contradicts his earlier claims that ISIS has been "defeated" in Syria. An administration official who held a White House background call with reporters Thursday afternoon did not deny that a contingent of ISIS remains in Syria, and some Republicans in Congress have also said the president's claim that ISIS is defeated is simply untrue.

Republican Sen. Lindsey Graham, an ally of the president who has fiercely criticized his decision to pull out of Syria and for failing to consult Congress on it, disputed the president's assertion that Russia, Iran and Syria are unhappy with the president's decision as "fake news."

It is not FAKE NEWS that Russia, Iran, and Assad are unhappy about our decision to withdraw from Syria. They are ECSTATIC! https://t.co/7cZgEDBbdT — Lindsey Graham (@LindseyGrahamSC) December 20, 2018

The day before, Graham also tweeted, "With all due respect, ISIS is not defeated in Syria, Iraq, and after just returning from visiting there -- certainly not Afghanistan."

Key Republicans in Congress, including Graham and Sen. Bob Corker, a frequent Trump critic who heads the Senate Foreign Relations Committee, have blasted the president's rationale for backing out of Syria — and for leaving them out of the loop.

Graham, holding a press conference with reporters Thursday, said he doesn't want to hear anything more about how much leaders love the troops — he wants to see a reconsideration of the action Mr. Trump took. Graham said the last-minute decision has "rattled the world."

"There are a lot of broken hearts of Americans," Graham said of the decision, adding, "I don't know where it came from, but it needs to be reconsidered."

Corker told reporters on Capitol Hill Wednesday a previously scheduled meeting with the president was canceled Wednesday while he was waiting for the president at the White House.

"I doubt there is anybody in the Republican caucus in the Senate that just isn't stunned by this precipitous decision," Corker told reporters Thursday. "It's just like he woke up in the morning and made it."

Corker also called Mr. Trump's decision to pull out of Syria just like — or perhaps, worse — than former President Barack Obama's decision to pull troops from Iraq, a decision Mr. Trump blasted at the time.

Iraq in political turmoil one day after we leave---I told you so. — Donald J. Trump (@realDonaldTrump) December 20, 2011

It's unclear how the troop withdrawal in Syria will actually be implemented. A senior administration official Wednesday was unable to tell reporters the conference call how many troops have already been sent home from Syria, if any, or what the next phase is in the campaign there, referring questions to the Department of Defense.