WASHINGTON (NEXSTAR) — President Joe Biden says he will pull all remaining United States troops out of Afghanistan later this year, but his announcement already has some lawmakers on Capitol Hill concerned over whether the move will create a space for terror groups to move back in.

The president announced Wednesday he plans to bring all American troops home by Sept. 11 of this year, saying “it’s time to end America’s longest war.” Sept. 11, 2021 will mark 20 years since the 9/11 terror attack that sparked the war.

“Our presence in Afghanistan should be focused on the reason we went in the first place – to ensure Afghanistan would not be used as a base from which to attack our homeland again,” Biden said.

He delivered the news from the same room that President George W. Bush used to announce the beginning of the war. Biden noted that he spoke with the former president ahead of his decision.

“While he and I have had many disagreements over policy throughout the years, we’re absolutely united in our respect and support for the valor, courage and integrity of the women and men of the armed forces who served,” President Biden said.

Former President Barack Obama also weighed in on Wednesday, posting a statement to Twitter supporting Biden’s move.

“After nearly two decades in Afghanistan, it’s time to recognize that we have accomplished all that we can militarily, and bring our remaining troops home,” Obama wrote. “I support @POTUS’s bold leadership in building our nation at home and restoring our standing around the world.”

Meanwhile, lawmakers on Capitol Hill say they want the war to end, but think it’s a bad idea to leave Afghanistan entirely.

“Without sustained pressure on these terror groups, they reform, they rebuild and then they try to kill Americans,” Sen. Marco Rubio, R-Fla., said.

Both of Florida’s U.S. senators – Rubio and his fellow Republican Rick Scott – say they’re worried about allowing space for the resurgence of terrorist groups.

“Hopefully the president is talking to our allies and making sure that doesn’t happen,” Sen. Scott said.

Sen. Lindsey Graham says he tried to meet with President Biden last month to encourage him to leave a presence in the region.

“This is a bad decision that is going to come back to haunt us,” the South Carolina Republican said.

The White House says diplomatic and humanization efforts will continue, but there will be no military physically present.