A Downing Street spokesman said:
The Prime Minister spoke to the President of Kenya, Uhuru Kenyatta, late this afternoon about the attack at Westgate shopping centre in Nairobi.
President Kenyatta updated the Prime Minister on the current situation and explained that Kenyan security forces were bringing the situation under control.
The Prime Minister passed on his sincere condolences and assured President Kenyatta that our thoughts were with him and all the people of Kenya at this difficult time.
The Prime Minister said we were ready to provide any assistance we could.