“I do not think the crowds we have seen in Iran are fabricated, everyone can now see how serious this situation is,” he said.
Mr Burt said the Government should avoid taking sides and ally with the EU to call for reduced tensions.
President Trump said Soleimani was targeted because he was plotting the deaths of Americans.
General Qasem Soleimani was killed in a US drone strike
AP
Salami told crowds in Kerman he had been “martyred”, adding: “We will take revenge. We will set ablaze where they like.”
According to a semi-official Iranian news agency, Tehran has plans for 13 acts of revenge.
It quoted Ali Shamkhani, the secretary of Iran’s Supreme National Security Council, as saying: “If the US troops do not leave our region voluntarily and upright, we will do something to carry their bodies horizontally out.”
General Sir Richard Barrons, a former commander of Joint Forces Command, said an apparent leak of British contingency planning to evacuate personnel from Iraq looked “clumsy”.
There was confusion in Washington over reports that the US is pulling out its troops from Iraq. A letter setting out details was said to have been drafted in error. US Defence Secretary Mark Esper told reporters: “There’s been no decision whatsoever to leave Iraq. I don’t know what that letter is.”
President Trump responded to Iran’s anger by warning that the US was ready to strike back in a “disproportionate” manner.
He has also threatened to hit cultural sites, a move that Britain and other countries say would be unlawful.
The Foreign Office would not confirm reports that it was scaling back staffing at British embassies in the Middle East.
“The British embassies in both Baghdad and Tehran are open,” said a spokesman. “The safety and security of our staff is of paramount importance and we keep our security posture under regular review.”
Defence Secretary Ben Wallace is due to update MPs — returning to Westminster following their Christmas break — on the latest situation in the region.
Mr Raab is due to fly to Washington later this week to meet Secretary of State Mike Pompeo.
