U.S. President Donald Trump wrapped up his two-hour-long meeting with senior U.S. military commanders at the Pentagon on Thursday (July 20), where he was briefed on the fight against Daesh and the 16-year long engagement in Afghanistan.

Trump said they were "tremendous people" but would not disclose what military decisions had been taken during the two-hour meeting.

Trump - who met with Defense Secretary James Mattis and Chairman of the Joint Chiefs of Staff Gen. Joseph Dunford - said "we'll see," when asked prior to the meeting if he was planning on sending more troops to Afghanistan.

He then added, "We're doing very well against ISIS. ISIS is falling fast. Very fast."

When asked about an announcement on troop levels in Afghanistan, Trump said, "you'll be hearing," but did not elaborate. He also ignored a question about Attorney General Jeff Sessions.

Trump arrived at the Pentagon along with Vice President Pence, Treasury Secretary Steven Mnuchin and Secretary of State Rex Tillerson, the Associated Press reported. His son-in-law and senior adviser Jared Kushner also attended.

The Defense Department for several months has been working on a new strategy for the 16-year conflict in Afghanistan. Mattis is expected to authorize an additional 4,000 troops to be sent to the country - an authority Trump gave him last month.

The defense chief on Wednesday briefed the full Senate on the current fight against ISIS, but the meeting did not include the new strategy for Afghanistan Mattis had promised would come this month. 

About 8,400 U.S. troops are currently stationed in Afghanistan in a train, advice and assist capacity.