Boris Johnson has warned Iran not to repeat "reckless and dangerous" attacks after ballistic missiles were fired at air bases in Iraq where coalition forces are stationed.
The prime minister called for "urgent de-escalation" after strikes on bases in Irbil and al Asad.
He said there were no UK casualties "as far as we can tell".
Iran's Revolutionary Guard said the strikes were in retaliation for the death of General Qasem Soleimani.
He was killed outside Baghdad airport on Friday in a missile strike ordered by US President Donald Trump.