Britain on Monday urged Iran to stop sending weapons into Yemen and instead use its influence to end the conflict, as the Saudi-led coalition's military intervention enters its fourth year.
Saudi Arabia has been leading an aerial bombing campaign in support of the government and against the Iranian-backed Houthi rebels.
The United Nations has found Tehran in violation of an arms embargo on Yemen by failing to block supplies of missiles and drones to the Hputhis.
In a joint statement, Britain's Foreign Secretary Boris Johnson and International Development Secretary Penny Mordaunt urged Iran to change course.
"If Iran is genuinely committed to supporting a political solution in Yemen -- as it has publicly stated -- then it should stop sending in weapons which prolong the conflict, fuel regional tensions, and pose threats to international peace and security," they said in the statement.
"We question why Iran is spending significant revenue in a country with which it has no real historical ties or interests, rather than using its influence to end the conflict for the good of the Yemeni people."
The Houthis expelled pro-government forces from the capital Sanaa in September 2014 and went on to seize swathes of the impoverished Arabian Peninsula country.
This prompted the Arab Coalition to intervene militarily on March 26, 2015.