David Cameron has insisted he would not take "risks" with Britain's defences as he sought to dampen fears over the coalition's drastic austerity measures.

The Prime Minister said decisions in areas such as military capability were still being taken for the long term rather than to achieve immediate savings.

The comments came as the Conservatives kicked off their first conference since regaining power, with the gathering set to be dominated by looming public spending cuts.

It emerged last week that Defence Secretary Liam Fox had written privately to Mr Cameron warning that "draconian" reductions being demanded by the Treasury in his department would have "grave consequences".

But interviewed on the BBC's Andrew Marr Show, the premier played down the simmering row, saying Cabinet ministers were bound to make "very, very strong representations".

"He knows and I know that I am passionately pro-defence, passionately pro our armed forces," Mr Cameron said.

"I will not take any risks with Britain's defence. But I want us to have something that the last government did not do - a proper review to make sure we are spending money in a way that protects our country for the future. That is what this is about."