Trump's remarks suggested he believed that the U.S. military-backed campaign against ISIS in Syria was close to being complete. The Pentagon and State Department, however, have suggested a much longer-term effort is necessary.
"It's time," Trump told reporters.
"We were very successful against (ISIS). We'll be successful against anybody militarily. But sometimes it's time to come back home, and we're thinking about that very seriously."
The United States has about 2,000 forces in Syria who are battling the group.
U.S. Army General Joseph Votel, who oversees U.S. troops in the Middle East as the head of Central Command, estimated on Tuesday that more than 90 percent of the group's territory in Syria had been taken back from the terrorists.
Trump estimated the percentage of territory recaptured in Iraq and Syria at "almost 100 percent," and, in a sign of his complicated views on the campaign, also said: "We will not rest until ISIS is gone."
Brett McGurk, the special U.S. envoy for the global coalition against ISIS, speaking alongside Votel across town on Tuesday, said the U.S. fight against ISIS was not over.
"We are in Syria to fight ISIS. That is our mission and our mission isn't over and we are going to complete that mission," McGurk said.
McGurk acknowledged a review was underway to ensure U.S. taxpayer dollars were well spent, when asked about media reports that Trump had ordered the State Department to freeze more than $200 million in funds for recovery efforts in Syria.
Votel said he saw a U.S. military role in stabilization efforts in Syria.
"The hard part, I think, is in front of us, and that is stabilizing these areas, consolidating our gains, getting people back into their homes," Votel said.
"There is a military role in this. Certainly in the stabilization phase."
(Reporting by Phil Stewart, Idrees Ali, Lesley Wroughton, and Lisa Lambert; Editing by James Dalgleish)