Iran’s foreign minister, Abbas Araghchi, says he is backing comments by Germany’s president, Frank-Walter Steinmeier, after Steinmeier said the US-Israel war on Iran is a violation of international law.

In a post on social media, Araghchi says: “Credit to President Steinmeier for condemning the violations against Iranians.” He adds that “those who value the rule of law should also speak up”.

Steinmeier’s remarks are presented as a rare and direct criticism of Donald Trump’s foreign policy. He is also said to have argued that the conflict marks a rupture in Germany’s ties with its most important post-war ally.

As German president, Steinmeier holds a largely ceremonial office, which gives him more room to speak openly than government ministers. Chancellor Friedrich Merz, by contrast, has so far avoided answering directly when asked about the legality of the war.