Israel and Iran exchanged strikes a week into their air war on Friday as US President Donald Trump weighed US military involvement and new diplomatic efforts appeared to be under way.

Trump has been weighing whether to attack Iran by striking its well-defended Fordo uranium enrichment facility, which is buried under a mountain and widely considered to be out of reach of all but America’s “bunker-buster” bombs.

He said he would decide within two weeks whether the US military will get directly involved in the war given the “substantial chance” for renewed negotiations over Tehran’s nuclear programme.

Iran’s Foreign Minister Abbas Araghchi appeared headed to Geneva for meetings with the European Union’s top diplomat and counterparts from the United Kingdom, France and Germany.

A plane with his usual call sign took off from the Turkish city of Van, near the Iranian border, flight-tracking data from FlightRadar24 showed. Iran typically acknowledges his departure hours afterwards.