The Home Secretary warned of a "clash of civilizations" between the West and Islamic extremists as she launched a package of new anti-terror measures on 23 March 2015. Theresa May said there is "increasing evidence" that a small but significant number of people living in Britain "reject our values".

"Thousands of 'honour' crimes committed every year and hundreds of British citizens who have travelled to fight in Syria and Iraq. We've been clear all along that the government's counter-extremism strategy must seek to destroy extremism in all its forms," the top Tory declared.

"But it's obvious from the evidence that the most serious and wide-spread form of extremism we need to confront is Islamist extremism. Islamist extremists believe in a clash of civilisations. They promote a fundamental incompatibility between Islamic and Western values, an inevitable divide between 'them and us'.

"They demand a caliphate or a new Islamic State, governed by a harsh interpretation of Sharia law. They utterly reject British and Western values, including democracy, the rule of law and equality between citizens," said May.

The Home Secretary called on the British Muslim community to join in a "partnership" with the government to tackle so called "hate preachers". May also announced that a future Conservative government would hold a probe into the application of sharia law in the UK.

But Labour attacked the Home Secretary and claimed that her counter-terrorism strategy had "failed".

"Every day we hear of more British citizens being groomed, radicalised and trying to travel to Syria to join a vile barbaric organisation," said Yvette Cooper, Labour's shadow home secretary.

"Yet May's strategy has failed to tackle the problem. She has had five years as Home Secretary to do all these things, yet too many of her promises are the opposite of what she has done in government."

Cooper added: "She says she wants stronger powers but she abolished control orders and relocation powers which made it easier for terrorists to organise and send people to Syria. Once again, five years on, she has been forced to backtrack and reverse her decision."