Cameron to back new security body

The Council would oversee security aspects of foreign and defence policy, but unlike the American model would also include "homeland security" issues like tackling home-grown extremism and encouraging community cohesion.

Mr Cameron's security spokeswoman Baroness Neville-Jones said that the Tory leader would also call for the creation of a special unit of several thousand troops for deployment in case of national emergency and disaster.

Readiness for domestic emergencies must take priority over interventions in foreign flashpoints like Kosovo, and Britain should be prepared to scale back its international presence in order to improve security at home, she said.

Lady Neville-Jones - the former head of the Government's Joint Intelligence Committee - said that the policy of multiculturalism pursued over recent decades had fostered separatism by "favouring" different ethnic communities on the basis of their difference from the mainstream.

She called for a change in direction to ensure equal rights and responsibilities for all under a single law - and criticised Archbishop of Canterbury Rowan Williams for suggesting that elements of Sharia law could be introduced in the UK.

Setting out Tory plans for a new overarching security body, Lady Neville-Jones told BBC1's Andrew Marr Show: "We would like to do something which takes its inspiration from the American model of the National Security Council. But we would include - unlike the Americans - all the aspects which they call homeland security, all the internal stuff as well.

"We want to try to bring foreign policy, defence policy, internal security issues which dominate so much of out consciousness now, and also things that really go to the underlying causes that lead people into the paths that might take them off into terrorism - the issues of national cohesion."

Lady Neville-Jones said that the head of MI5 had made it clear that the radicalisation of Britain's Muslim community was increasing and that the authorities had been "very slow to grasp the underlying causes" which led individuals into supporting extremism and separatism.

Multiculturalism had turned into a system of "people being favoured because of their particular characteristics" rather than "people being given equal opportunities despite their differences", she said.