Earlier, The Guardian reported that the UK was reportedly not informed in advance of the US airstrike aimed against Iran's Major General Qasem Soleimani.
The UK Labour Party's leader Jeremy Corbyn has demanded an urgent meeting of the Privy Council over the US killing of Iran's Major General Qasem Soleimani and following the Pentagon's announcement that it will send 3,000 more troops to the Middle East.
Mr Corbyn wrote a letter to Prime Minister Boris Johnson, outlining a series of questions that he thinks should be discussed, including measures the UK should take to ensure the safety of its nationals.
"Given the serious nature of the issues now faced by our country and indeed the world as a consequence of the US attack, I would welcome a prompt response to this request and stand ready to attend any briefing meeting as soon as arranged," Corbyn wrote.
The Labour leader described the attack as an "assassination", calling on the UK government to resist the "belligerent actions" from the US.
Meanwhile, Boris Johnson is reported to have been on holiday on the private Caribbean island of Mustique and Number 10 has not yet said when he is due to return.
On Friday, The Guardian reported, citing the chair of the foreign affairs committee Tom Tugendhat, that London was not informed in advance about the US airstrike against Soleimani.
"...it’s been a pattern, sadly, which has been a bit of a shame, that the US administration of late has not shared with us, and that is a matter of concern," Tugendhat told BBC News.
Commenting on the US killing of Iran's top military official Soleimani, UK Foreign Secretary Dominic Raab called on all parties to de-escalate the situation, adding that "further conflict is in none of our interests". The Foreign Office also warned UK citizens on Saturday against travelling to Iraq and Iran in order to avoid the risk of being detained or attested.