US ambassador to Kenya Prudence Bushnell described the money as a symbolic gesture of friendship which would help people needing medical, psychological and economic help.

"I'm not going to sit here and tell anybody that $37m is going to erase the pain, ease the anger or put back the shattered lives of thousands of people," she said at a news conference held to mark the signing of the aid agreement.

Kenyan Finance Minister Francis Masakhalia replied that the money would not fully compensate the country or the victims but would go a long way to assist recovery and rehabilitation.

'Colossal damage'

Lasting scars: Most killed were Kenyans

"The economic and social damage of the bomb blast was colossal," Mr Masakhalia said.

"A lot of lives were lost and many other people suffered permanent disabilities."

More than 200 people were killed in the attack - the majority of them Kenyans. More than 5,000 were wounded.