Lynton Crosby has admitted that his decision to manage the Conservative general election campaign is a risk.

Crosby, who is Michael Howard's chief strategist, helped deliver four straight victories for John Howard, the Australian prime minister.

Interviewed by "The Australian", Crosby said: "I am optimistic that the Conservative Party can do very well, and they can win. But life is not without risk.

"Getting up in the morning has a risk, crossing the road has a risk."

He added: "I always have the view of life that you give it your best shot and people will make their judgments, if they are not happy then so be it, it doesn't bother me much."

He also refused to elaborate on reports of tension with Lord Saatchi and Liam Fox, the party's co-chairmen.

"Maurice Saatchi is still a great ad man and he understands how to communicate with people, and Liam Fox I think is a very good party frontman in terms of the media and carrying the message."

Meanwhile, David Cameron, the party's head of policy, has warned that the Tories will lose the next election unless they can convince the electorate they are prepared for government.

Interviewed in the Independent, Cameron says: "In a way it's quite like 1992 when people wanted to throw the Tories out and they looked at Labour and said: 'no you are not ready'."

"This time I think they want to throw Labour out. They are looking at us and that is [why] we have got to show that we are ready."