Alan Milburn has pledged to run an "aggressive" election campaign against Conservative policies.

The comments came after a political meeting of the Cabinet, where ministers agreed the wording of the election slogan.

Labour will campaign on the simple message of "Britain: Forward not back".

The election would "boil down" to a choice between Labour and the Tories, he told a press briefing.

Milburn said the words "sum up the mood and desire of the country".

The chief election strategist was also dismissive of the Liberal Democrats, who will target once safe Labour territory.

The government's campaign is set to focus on the three themes of the economy, modernising public services, and crime and asylum.

The choices reflect an assessment that domestic issues rather than foreign policy issues such as Iraq will decide the outcome of the forthcoming poll.

While the economy is seen as a Labour strong point, there will be surprise that the party is prepared to give a high profile role to its policies on asylum.

Recent tough Conservative policy announcements on the issue were backed by a large proportion of voters, according to recent polls.

With all the Westminster parties now gearing up their campaigns, there has been speculation that the next election could be called even earlier than the May 5 previously assumed.

"People know we are not perfect, they know we have not done everything we or they would want us to," Milburn conceded.

"But they believe the country is moving in the right direction and they don't want to reverse course."

The prime minister's role during  the campaign will see him "spending more time out of London than in it, but in Britain not overseas" Milburn disclosed.

"He will be leading the domestic debate from the front, listening, taking the flak."

With the party set to run newspaper adverts attacking the Tories, Milburn added: "I make no apology for an aggressive campaign against them."