Russian President Vladimir Putin said Thursday he welcomes President Donald Trump’s decision to withdraw U.S. military forces from Syria.

Putin said during his annual news conference Thursday that, "If the U.S. decided to withdraw its contingent, it has done the right thing," according to The Associated Press.

Putin reaffirmed the long-held Russian argument that the U.S. presence in Syria is illegitimate because it hasn’t been vetted by the U.N. Security Council or approved by Syrian President Bashar Assad’s government. The pullout is also likely to strengthen Russia's role in Syria's future.

Trump announced Wednesday that would pull all 2,000 U.S. troops out of Syria and declared victory over the Islamic State group, or ISIS, in a move that stunned Republicans in Congress.

"Donald's right, and I agree with him," Putin said Thursday, according to The New York Times.

While praising the decision, Putin also expressed skepticism that a withdrawal of U.S. troops would actually take place, pointing to a 2014 announcement that American forces planned to pull out of Afghanistan, the Times reported.

“We don’t’ see any signs yet of the withdrawal of U.S. troops,” he said, according to the newspaper. “How long has the United States been in Afghanistan? Seventeen years? And almost every year they say they’re pulling out their troops.”

A senior Trump administration official confirmed the president’s plan Wednesday, although no specifics were immediately available.

The U.S. began airstrikes in Syria in 2014, and ground troops moved in the following year to battle the Islamic State and train Syrian rebels in a country torn apart by civil war.

Trump said early Thursday in a tweet that his decision “was no surprise.”

“I’ve been campaigning on it for years, and six months ago, when I very publicly wanted to do it, I agreed to stay longer,” Trump said. “Russia, Iran, Syria & others are the local enemy of ISIS. We were doing there work. Time to come home & rebuild.”

The Associated Press contributed to this report.