PRESSURE on Labour mounted today to scrap King Charles’s state visit to Washington because of the US war of aggression against Iran.

Campaigners and senior MPs united to demand that PM Sir Keir Starmer pull the plug on the trip as the “special relationship” with Donald Trump’s US unravels.

Islington MP Emily Thornberry, chair of the Commons foreign affairs committee, said it would be “safer to delay” the royal visit, scheduled for next month.

Any postponement would, of course, risk further inflaming the mercurial US president, who is presently aiming insults at Sir Keir on almost a daily basis.

Dame Emily said: “The most important thing if it was to go ahead next month, and the dates haven’t been confirmed, it would go ahead against the backdrop of a war.

“And that I think is quite difficult. And the last thing we want is have their majesties embarrassed. I don’t know what the discussions are, I don’t know what the programme would involve.

“But I think it needs to be thought through very carefully as to whether or not it’s appropriate to go ahead now or maybe have a limited programme or delay it. But we can’t just pretend there isn’t a background of war.”

And the Stop Trump Coalition launched an online petition urging the government to stop the visit.

The coalition said: “At this fragile moment where Trump is conducting an illegal war on Iran – and dragging the world into it – the King’s visit would serve as a statement of support for this illegal war. It must not go ahead.

“The King should not pay Trump a royal visit when Trump’s recent attacks on Iran, killing civilians, demonstrate his brazen disregard for international law and human rights.

“Appeasing Trump has already seen the UK allow the US to use military bases on British soil to conduct bombing raids on Iran — making us complicit in this illegal war.

“Trump has also previously threatened to annex Canada – where the King is head of state. This threat must be taken seriously after his attack on Venezuela and threats towards Greenland.

“The UK should be strengthening relationships around the world to make new alliances that reduce our dependency on the US, not further cosying up to Trump.”

The US president has branded Sir Keir’s approach to his aggression against Iran “terrible” and said the premier is “no Winston Churchill” after an initial refusal — speedily reversed — to allow British bases to be used for the attack.

He has been further incensed by British reluctance to provide ships to help reopen the Strait of Hormuz, closed because of the war, and has threatened the future of Nato as a result.

The British government, while escalating its military involvement in the conflict to maintain its own regional interests, believes Trump has no idea why he started the war nor how he will end it.

After more than a year of sycophancy towards the US president, ministers are becoming a little bolder.  Treasury number two Dan Tomlinson dismissed Mr Trump’s latest remarks today as “froth.”

He added: “We’re not rushing to engage in this war. The prime minister was clear that he didn’t want to be part of trying to change the regime in Iran from the skies and I think that approach is being vindicated over time.”

They are fortified by public opinion, which shows broad opposition to the war. Moreover a YouGov survey revealed that more people believe the royal visit should be cancelled than think it should go ahead.

However, Sir Keir may be reluctant to further antagonise the president, who loves the pomp and circumstance associated with British royalty and has twice paid state visits to Britain.