WASHINGTON — President Trump declared on Thursday that “we just took over 100 percent” of territory controlled by the Islamic State in Syria — a claim that reports from the battle front suggested was 100 percent untrue.

“You kept hearing it was 90 percent, 92 percent, the caliphate in Syria. Now it’s 100 percent, we just took over,” Mr. Trump said in remarks to American troops in Alaska. “Now it’s 100 percent, we just took over 100 percent caliphate. That means the area of the land. We just have 100 percent.”

“So that’s good.”

Over the past month, American forces have been working with Syrian fighters to seize the last square mile of Islamic State territory — the riverside village of Baghuz on the border with Iraq. Taking and holding terrain in any military operation can be a difficult task, especially against extremists who are willing to face death instead of surrender.



[Update: ISIS caliphate crumbles as last village in Syria falls.]

The battle was continuing on Thursday when officials with the Syrian Democratic Forces, an American-backed militia of Kurdish and Arab fighters, were told of Mr. Trump’s announcement.