The Government is set to take a firmer stance against Muslims who fail to oppose Islamist extremism.

In a speech to be delivered to an audience of Muslim men and women in Birmingham, David Cameron is expected to announce that only those in the Muslim community willing to take a stand against jihadist violence will be supported and those who “walk up to the border of illegality” will be denounced.

A Downing Street source told The Independent on Sunday: “There are people in the Muslim community who walk up to the border of illegality with the aim of radicalising others – they are the equivalent of David Irving denying the Holocaust.

“There are Muslims who say they are not advocating violence,” said the source, but who still deny the Holocaust, question Israel’s right to exist, and whether men and women and Jews and Muslims should mix.

David Cameron: ‘We’ve got to call out and confront unacceptable views’ (Getty)

The Prime Minister reiterated his position on beating terrorism in an interview with NBC’s Meet the Press.

“We have to attack directly this Islamist extremist ideology that is poisoning young minds, including young minds in Britain and America,” he said. The “narrative of extremism” must be defeated, he added.

“People who say, ‘Well, of course I don’t support terrorism. But a caliphate, is that such a bad idea?’ Or people who say, ‘Do you know what? Christians and Muslims, we can’t really live together. And suicide bombing [is] alright in Israel, even if it’s not alright in America.’

“These are unacceptable views. We’ve got to call them out and confront them,” said Mr Cameron. “We’ve got to defeat the narrative of extremism, even when it’s not connected to the violence.

“It’s the narrative that is the jumping-off point for these young people to then go and join this dreadful death cult in Iraq and Syria,” he added.