Britain and France extended the closure of their embassies in Yemen on Monday after a US warning of a possible militant attack in the region, and the Arab state said it was stepping up security at ports and airports.

Britain, which had said last week that it would close its embassy in Yemen on Aug 4 and 5, said on Monday the mission would remain closed and reopen on Thursday.

France, which closed its Yemen embassy on Sunday, said the mission would also reopen on Thursday.

Security in Yemen is a global concern as it is home to one of the most active wings of al-Qaida and shares a long border with Saudi Arabia, a US ally and the world's top oil exporter.

The Yemeni interior ministry said late on Sunday it had ordered officials to increase security at ports and airports, as well as vital institutions, oil pipelines and electricity cables during the Eid holidays, which end at the weekend.

Reuters