"We're going to cut way down, and we're cutting a lot further than 5000," Trump told reporters in Florida.
A US administration review is likely to cancel the decision to station a battalion of Tomahawk missiles in Germany as part of NATO's planned militarization against Russia, according to a Financial Times report.
Trump has previously sharply criticized Merz over his stance on Iran and nuclear weapons, saying that the United States is considering the possibility of reducing its contingent in Germany, and the decision would be made soon.