Mr Cameron assured President Medvedev of his complete support and said the Russian authorities could count on Britain for any assistance.
A Number 10 spokeswoman said:
The Prime Minister spoke to President Medvedev of Russia this evening.
The Prime Minister utterly condemned today’s explosion at Domodedovo airport. He offered his condolences and sympathies to all those who had been affected by what he described as an ‘appalling attack’.
The Prime Minister assured President Medvedev of his complete support and said that the Russian authorities could count on Britain for any assistance they needed.
The Prime Minister made clear that the people of Britain stood with the people of Russia in the face of these events and said that ‘we should never allow the terrorists to win’.
Foreign Secretary William Hague described the attack as an unjustified “mindless act of terrorism”.
Mr Hague said:
As soon as we learned of the explosion the Foreign Office sent a consular team to the airport to liaise with the Russian authorities and provide assistance to any British national that might have been caught up in the blast,” he added.
We will continue to work around the clock in Moscow and London to ensure that any British National involved is given the support they need.
Read more: Foreign Secretary condemns terrorist bombing at Russian airport