The British embassy in Cairo has been closed to the public due to unspecified security concerns.

No details were given of the nature of the fears, but officials said they hoped public services at the mission would resume as soon as possible.

The UK Foreign Office travel advice for Egypt warns there is a "high threat from terrorism".

"Terrorists continue to plan attacks in Egypt. Attacks could be indiscriminate and occur without prior warning. Foreigners could be targeted in tourist resorts or other locations frequented by foreigners," it says.

"Previous attacks have almost exclusively targeted the security forces, their facilities and other government buildings."

The British Consulate-General's office in Alexandria remains open.

Egypt has been battling an Islamist insurgency that predominantly carries out attacks in the Sinai Peninsula, near the border with Israel, Gaza and the Suez Canal.

Hundreds of police and soldiers have been killed over the past year and on Monday the Ansar Beit al Maqdis group, which has sworn allegiance to Islamic State, claimed it was behind the killing of an American oil engineer in the western desert in August.

Cairo has also been targeted by small-scale bombings, which have usually caused only limited injuries.

The embassy was closed as airport officials launched tough new rules requiring Egyptians to have a permit to travel to Turkey, a move aimed at stopping people joining Islamist militant groups in Iraq and Syria.

Egyptians already need prior permission to travel to Syria, Iraq and Jordan.