From [1] The Scotsman, with thanks to Kemaste:

BRITAIN closed its embassy in Yemen yesterday due to security concerns and warned that "terrorists" were in the final stages of planning attacks against Western targets in the Arab state.

"The British embassy will be closed on 5 January in response to specific security concerns," an embassy advisory said, but did not elaborate.

"As at 30 December, there is specific information that terrorists are in the final stages of planning attacks against British targets and other Western targets in Yemen," it said.

It advised British citizens to be particularly vigilant in places frequented by foreigners such as hotels.