What is the extent of the UK’s involvement in the Middle East war?

What is likely to happen now that the US has been given permission to use British bases for a ‘specific and limited defensive purpose’

Britain has rapidly been dragged into the war in the Middle East, with Keir Starmer concluding that involvement was inevitable because of Iranian retaliation, regional alliances – and a repeated US request for help. In doing so, the prime minister has changed his mind and concluded that what was once an illegal war has become in some respects, legal.

How has the UK prepared for the possibility of US and Israeli strikes on Iran?

Over the past six weeks, the UK had been building up some military assets in the Middle East, to protect its existing base at Akrotiri in Cyprus and to help key allies in the Gulf. A joint UK-Qatari squadron relocated from Lincolnshire to Qatar in January, ready to act in self-defence if the Gulf country and others in the region were attacked.

The expectation was that if the US and Israel did attack Iran, then Tehran would most likely lash out, and launch ballistic missiles and drones at US bases in the region (where British troops are often co-located) and at a range of regional allies. RAF Typhoons in Qatar and F-35s and Typhoons in Akrotiri would be able to shoot down incoming drones and help defend allies if attacked.

Last month Starmer refused a request from Donald Trump to allow two British bases – RAF Fairford in Gloucestershire and Diego Garcia in the Indian Ocean to be used as part of the US-Israeli attack. Trump said on Monday he was “very disappointed” with that decision in an interview with the Telegraph, adding “it sounds like he was worried about the legality”.

What is the UK’s position now?

In a video address on Sunday night, Starmer announced a new policy. The UK would, after all, give the US permission to use British bases for what the prime minister said was a “specific and limited defensive purpose” – to destroy Iranian missiles before they have taken off by bombing their storage depots or launchers.

The calculus on Sunday was that this involvement was legal under international law because the UK was participating in the self-defence of allied nations. Iran has retaliated against nine countries so far, with missiles and drones: Israel, Jordan, Kuwait, Bahrain, the UAE, Qatar, Saudi Arabia, Oman and Cyprus.

What could the UK’s missions look like?

Starmer did not provide much more detail. Military analysts said the most likely immediate scenario was that the UK would allow the US to use Fairford and Diego Garcia to bomb Iran’s “missile cities”. These are five or possibly more sites cut into Iran’s mountains at depths of perhaps 500 metres where high-speed ballistic missiles, Iran’s most dangerous weapons, are stored and can be launched from.

Targeting them effectively would probably require the use of US heavy bombers using so called bunker-buster munitions, carried by B-2 stealth bombers or B-52s operating from Fairford or Diego Garcia, simply preferred by the US air force because they are closer to Iran than bases in the US itself.

Would that be the limit of UK involvement?

Additional Iranian retaliation against the UK or its allies could easily draw Britain in further. A string of drones appear to be have been targeting the RAF base at Akrotiri on Sunday and again on Monday, with one hitting on Sunday night. The UK may seek to retaliate directly against whoever it thinks has been launching them.

More broadly, the US may well ask the UK for further military support if the air assault on Iran continues. Starmer has now shown that Britain is willing to be flexible if it believes a deeper military effort can be characterised as defensive. If the war escalates, or attacks mount, the UK’s commitment to the conflict may well deepen.