Dominic Raab has condemned a ballistic missile attack by Iran on air bases in Iraq that house coalition forces, including British personnel.
The foreign secretary urged Iran not to repeat “reckless and dangerous attacks” after strikes on bases in Irbil and al Asad, west of Baghdad.
The Ministry of Defence said there were no UK casualties.
Iran’s Revolutionary Guard said the action was in retaliation for the death of General Qasem Soleimani on Friday.
He was killed outside Baghdad airport in a missile strike ordered by US President Donald Trump.
Mr Raab said he was concerned by reports of casualties and a war in the Middle East would only benefit terrorist groups.
Speaking on BBC Breakfast, Brexit Secretary Stephen Barclay stressed that all parties in the crisis “need to de-escalate”.
“It’s in no side’s interest to see war,” he said.
Mr Barclay added that Prime Minister Boris Johnson would be updating the House of Commons later, and would also discuss the situation at a meeting with EU Commission President Ursula von der Leyen on Wednesday.
There are around 400 UK troops stationed in Iraq, primarily to assist in defeating IS.
More than a dozen missiles were fired from Iranian territories into Iraq at about 2:00am local time (10.30 GMT).
On Tuesday, the UK put the Royal Navy and military helicopters on standby in the Gulf amid the rising tensions in the Middle East.
The government said non-essential UK personnel had also been moved out of the Iraqi capital Baghdad.