Sri Lanka, June 23 -- The US and the UK have told their citizens in Qatar to shelter in place "until further notice".

The US embassy in Qatar suggested in a notice online that Americans do so "out of an abundance of caution". The UK government said it was issuing its warning in response to the US alert.

The warnings come after the State Department told US citizens in international locations to "exercise increased caution," after the US bombed three nuclear sites in Iran on Saturday. Iran has threatened to retaliate.

In a statement, Qatar's Ministry of Foreign Affairs said a number of countries were urging precautions, but the embassy notice did "not necessarily reflect the existence of specific threats".

"The security situation in the...