WASHINGTON -- US President Donald Trump said Saturday the United States plans to withdraw "a lot further" than the 5,000 troops from Germany that the Pentagon had said earlier this week.

"We're going to cut way down, and we're cutting a lot further than 5,000," Trump told reporters before boarding Air Force One in the southeastern US state of Florida.

The Pentagon on Friday announced the withdrawal of about 5,000 US troops from Germany, which is expected to be completed over the next six to 12 months.

"This decision follows a thorough review of the (Defense) Department's force posture in Europe and is in recognition of theater requirements and conditions on the ground," chief Pentagon spokesman Sean Parnell said in a statement.

The North Atlantic Treaty Organization (NATO) said Saturday it was working with the United States to understand Washington's decision to withdraw troops from Germany, amid fresh tensions between the United States and Germany over the Middle East crisis.

Earlier, Trump hinted at a troop withdrawal after German Chancellor Friedrich Merz said Iran was "humiliating" Washington in negotiations to end the conflict between the two sides.

On Thursday, Trump said he may also reduce US military presence in Spain and Italy, while slamming European allies for not helping in the US-Israeli war against Iran.

Germany is prepared for a possible reduction of the US troops in the country, German Foreign Minister Johann Wadephul said Thursday.

More than 36,000 US active duty troops were deployed to bases throughout Germany as of the end of last year, along with nearly 1,500 reservists and 11,500 civilians, according to Defense Department data.

Germany also hosts the headquarters of US European Command and Africa Command, and its Ramstein Air Base serves as a key hub for US military operations.