US President Donald Trump has said that Washington is considering reducing the number of its troops in Germany, amid a row with German Chancellor Friedrich Merz over the Iran war.

"The United States is studying and reviewing the possible reduction of Troops in Germany, with a determination to be made over the next short period of time," Trump posted on social media.

The United States had more than 35,000 troops in Germany in 2024, although the number is now believed to be nearer 50,000.

Trump has made several statements calling for slashing troop numbers as part of his criticism of NATO, but Washington now appears determined to act.

Tensions over Iran

Hours before Trump's post, US Secretary of State Marco Rubio spoke with German Foreign Minister Johann Wadephul regarding freedom of navigation in the Strait.

Merz has become a target of Trump's ire after saying Iran is "humiliating" Washington at the negotiating table.

Trump countered that Merz "thinks it's OK for Iran to have a Nuclear Weapon."

The German leader played down the row, insisting: "The personal relationship between the American president and myself remains just as good as before."

However, he expressed doubts about the war, adding: "We in Germany and in Europe are suffering considerably from the consequences."

Washington appears to be considering other retaliatory measures against Western allies.

Reports suggest the US is considering suspending Spain from NATO and could review its position on Britain's control of the Falkland Islands.