The old US embassy was hit by a bomb blast in 1998

A warning from the US defence department on Friday raised the level of threat in Kenya to "high" and led to a regular one-day closure being extended.

Embassy spokesman Tom Hart said: "We are open today for business," but declined to give further information.

The embassy building has only been open for a few months. It replaced a mission destroyed in a car-bombing in 1998 which killed more than 200 people.

The diplomatic mission, in Nairobi's northern Gigiri suburb, had been closing regularly for one day a week after the US state department issued a beefed-up terrorism advisory on 15 May warning American citizens against all non-essential travel to Kenya.

Targeted

A decision to keep the offices closed on Monday and Tuesday followed increased warnings of an attack by US defence officials.

The new US embassy in Nairobi closes frequently

Kenya's National Security Minister, Chris Murungaru, denounced those warnings of an imminent attack as "wrong and misleading".

Targets in Kenya have been attacked twice in the last five years, with both blamed on Osama Bin Laden's al-Qaeda network.

The former US embassy in Nairobi was destroyed in a 1998 car-bomb attack in which 213 people - mostly Kenyans - were killed and more than 5,000 others injured.

Last November, an Israeli-owned hotel near Mombasa was bombed, killing at least 16 people.