The Prime Minister's official spokesman said that Mr Cameron's phone call with US President Barack Obama last around five minutes. He summarised the conversation as follows:
The Prime Minister congratulated President Obama on his election victory after a long and hard-fought campaign.
The president spoke of the outstanding partnership between the UK and the US and said he looked forward to working with the Prime Minister on a whole range of issues in the years ahead.
They agreed they would have a longer conversation soon on a number of strategic issues, including what more the international community can do to bring an end to the conflict in Syria and to support the development of peaceful democracy in Libya.
Now Barack Obama has secured four more years in the White House he must tackle the growing list of challenges facing America.
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Barack Obama has secured re-election as President on a night of drama in America. Here are the best pictures from election night: