British Prime Minister Gordon Brown has announced that the UK general election will take place on 6 May.
Mr Brown made the announcement surrounded by his cabinet on the steps of Downing Street.
He said he was seeking a 'clear and straightforward mandate' to carry on the work of economic recovery.
'Over the next few weeks I will go round the country - the length and breadth of our land - and I will take to the people a very straightforward and clear message - Britain is on the road to recovery and nothing we do should put that recovery at risk,' he said.
Mr Brown went Buckingham Palace this morning to ask Queen Elizabeth II to dissolve parliament.
Conservative leader David Cameron launched his party's campaign by saying: 'This country deserves a lot better than five more years of Gordon Brown and that is what we must offer.'
He added that this was the most important British election for a generation.
The electioneering has been going on for months, but today marks the official start of campaigning.
The key theme will be how to manage Britain's massive deficit as it emerges from recession. The arguments between the parties will be about how much to cut and how much to tax.
But it will be a campaign marked by two important differences: the widespread use of the internet to target voters and three US-style television debates by the party leaders.
The Conservative Party has been given a boost by two opinion polls published this morning giving them a ten-point lead over Labour.
That would be enough to give them a Commons majority.
However, a third poll in The Guardian gives them just a four-point lead, which would mean a hung parliament.
Such an outcome would see the Liberal Democrats play a crucial role in the formation of the next government.
Liberal Democrat leader Nick Clegg said it is not just a two-horse race between the main parties.
