New UK prime minister Burnham has approved US use of British bases to conduct limited strikes against Iran.

Iran's foreign ministry spokesman on Tuesday warned Bulgaria not to permit US forces to use Bulgarian territory for military action against Iran. Bulgaria has said it will seek parliamentary approval to host up to eight US tanker aircraft at a domestic airbase; Bulgaria is an EU and NATO member. State media quoted spokesman Baghaei saying any assistance enabling US attacks on Iran would amount to complicity in "aggression and war crimes" and urging Bulgaria not to become an accomplice.

Spot gold rose above $4,060/oz, up 1.29% on the day.