Iran is said to have rejected US calls to exercise restraint in its retaliation for the killing of Hamas’s political leader in Tehran as Israel braces for an imminent attack.

Over the weekend, Iranian officials told Arab diplomats they would not de-escalate, as requested by the US, but strike Israel even if it means war, sources told the Wall Street Journal.

It comes as Anthony Blinken, US secretary of state, told his G7 allies on Sunday that an attack by Iran and Hezbollah against Israel could start as early as Monday, three sources briefed on the call told Axios.

The US has raced to dispatch diplomatic and military support to help defend its ally, moving additional warplanes and warships to the region, while the UK said it had Royal Navy ships and RAF helicopters on standby.

Jordan sent its top diplomat on a rare trip to Iran on Sunday, while the Lebanese foreign minister headed to Cairo to diffuse tensions.

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