NICOLA Sturgeon has warned Boris Johnson not to allow the UK to be “dragged along” into Donald Trump’s war with Iran.

The First Minister’s comments came as hundreds of thousands gathered in Tehran for the funeral of Qasem Soleimani, the Iranian general killed by the US in a drone strike in Iraq on Friday.

The assassination, carried out on the orders of the American President, has led to threats of "severe revenge" and one senior Iranian commander has already promised to attack British troops.

Last night rockets believed to have been fired by an Iranian-backed militia injured six people in Baghdad’s Green Zone, where the US embassy is located.

That attack led to Trump threatening to take “disproportionate” action against the regime.

Already Iran has pulled back from the 2015 nuclear accord, and Iraq’s parliament has voted to expel all foreign military, including British soldiers.

The situation is tense, and yet Johnson only responded late on Sunday night, following his return from a 12-day holiday in the Caribbean. In a statement, the Prime Minister said he would “not lament” the killing of Soleimani.

He called for “de-escalation” on all sides.

Johnson said: “General Qasem Soleimani posed a threat to all our interests and was responsible for a pattern of disruptive, destabilising behaviour in the region.

“Given the leading role he has played in actions that have led to the deaths of thousands of innocent civilians and western personnel, we will not lament his death.

“It is clear, however, that all calls for retaliation or reprisals will simply lead to more violence in the region and they are in no one’s interest. We are in close contact with all sides to encourage de-escalation.”

Asked for her response, the First Minister called for “cool heads”.

She said: “Boris Johnson made a statement last night, perhaps belatedly, where he called for de-escalation, and as far as that goes that is welcome.

“There is a concern, and it’s a concern I share, that the UK government will allow itself to be dragged along with and simply give support to whatever the United States now decides is the right course of action, and I don’t think that is the right thing to do.

“We’ve seen previously the consequences of the UK simply going along with what the US wants in the Middle East and that is not the right thing to do right now.

“And I say all of that as I said at the outset as somebody who has no sympathy for the Iranian regime but this is about wider strategic interests. It’s about the safety of UK and other country’s citizens in the Middle East. And proper consideration, proper strategic thought and, as I said, cool heads are what matter more than anything right now.”

Britain, Germany and France issued a joint statement on Sunday urging all sides “to show utmost restraint and responsibility”.

Foreign Secretary Dominic Raab will update parliament when it returns tomorrow before flying to Washington for a meeting with Mike Pompeo, the US secretary of state.