Extracts from Cameron’s keynote speech that he is due to deliver in Birmingham later in the day were released to the media overnight.
The extremist ideology is the "struggle of our generation" that is often an outcome of some people living in isolated and deprived communities across the United Kingdom, the prime minister will say.
"For all our successes as a multi-racial, multi-faith democracy, we have to confront a tragic truth that there are people born and raised in this country who don't really identify with Britain and feel little or no attachment to other people here," Cameron is to say in his speech, according to the Guardian.
Cameron's speech comes as more and more Britons join militants in the Middle East as foreign fighters.
Some 700 UK citizens are estimated to have gone to Syria to fight alongside jihadists, including the Islamic State group, according to the Metropolitan Police. British intelligence services believe the actual figure is likely to be as high as 2,000.
