Iran’s foreign minister, Abbas Araghchi, says he welcomes comments by German President Frank-Walter Steinmeier describing the US and Israeli war on Iran as a breach of international law.

In a post on social media, Araghchi praises Steinmeier for condemning what he says are violations against Iranians. He also says others who support the rule of law should speak out.

Steinmeier’s intervention is presented as an unusually sharp criticism of Donald Trump’s foreign policy. It also signals a strain in German relations with the United States, described in the report as Berlin’s most important ally since the Second World War.

The German presidency is largely ceremonial, which gives Steinmeier more room than senior ministers to speak openly, according to the report. It adds that his stance is notably tougher than Chancellor Friedrich Merz’s, with Merz so far avoiding a clear answer on whether the war is lawful.