Thousands of European citizens have travelled to fight in Iraq and Syria, creating a grave threat to the British way of life, David Cameron has told MPs.

In a wide ranging statement following Saturday's European Council meeting, the Prime Minister outlined the Government's response - including tougher orders on suspected terrorists and new powers for police to temporarily seize passports at UK borders.

Stronger powers on the relocation of terror suspects are set to be re-introduced, Mr Cameron said, sparking Labour heckles about the abolition of control orders by the coalition Government.

Mr Cameron said the Government would continue to assess what measures it would take in Iraq and Syria, including humanitarian and potentially military actions, that were in the national interest.

He told MPs: "We have all been shocked and sickened by the barbarism we have witnessed in Iraq this summer, the widespread slaughter of Muslims by fellow Muslims, the vicious persecution of religious minorities such as Christians and Yazidis, the enslavement and raping of women and, of course, the beheading of American journalist James Foley with the voice of what seems to have been a British terrorist recorded on that video.

"The European Council conclusions could not be clearer, and I quote, the European Council believes the creation of an Islamic Caliphate in Iraq and and Syria and the Islamist extremism and export of terrorism on which it is based is a direct threat to every European country."

Mr Cameron said at least 500 had travelled from Britain to fight in the region - together with 700 from France, 400 from Germany and more from other states including America, Canada, Austria, Denmark, Spain, Sweden, Belgium, the Netherlands and Australia.

All European countries would take the necessary steps to tackle the problem, Mr Cameron told the Commons.

Mr Cameron continued: "We should be clear about the root cause of this threat: a poisonous ideology of Islamist extremism that believes in using the most brutal forms of terrorism to force people to accept a warped world view and to live in a medieval state.

"We should be clear this is nothing to do with Islam, which is a religion peacefully observed and devoutly observed by over a billion people and one that inspires countless acts of kindness every day."

Mr Cameron said a "tough, patient and comprehensive" approach was needed to defeat extremism and outlined to MPs how the Government planned to move forward.

He said aid, diplomacy and military force would be needed as part of a robust security response.

And the Prime Minister said: "Alongside a tough security response, there must also be the right political response. We know terrorist organisations thrive where there is political instability and weak or dysfunctional institutions.

"We must support the building blocks of free and open societies - in Syria it must mean a political transition and an end to (Bashar) Assad's brutality, which has allowed Isil to flourish.

"In Iraq, that must begin with a new and genuinely inclusive government capable of uniting all Iraqis.

"Britain will continue to consider what further role is in our national interest, including any further diplomatic, humanitarian or indeed military measures we might take."

The Prime Minister said a wide range of measures had already been taken to tackle threats on the domestic front, including passport seizures and stopping foreign nationals from returning to the UK.

He highlighted measures in the Immigration Act to remove British citizenship from dual nationals.

He added: "We are clear in principle that what we need is a targeted, discretionary power to allow us to exclude British nationals from the UK and we will work up proposals on this basis with our agencies, in line with our international obligations, and discuss the details on a cross-party basis."

And Mr Cameron told MPs he did not want to introduce "sweeping new powers", insisting the security services wanted a targeted approach reflecting a "forensic focus" on the threats.

He said: "Passports are not an automatic right. The Home Secretary already has the discretion to issue, revoke and refuse passports under the royal prerogative if there is reason to believe people are planning to take part in terrorist-related activity.

"But when police suspect a traveller at the border, they are not currently able to apply for the royal prerogative and so only have limited stop-and-search powers. We will introduce specific and targeted legislation to fill this gap by providing the police with a temporary power to seize a passport at the border, during which time they will be able to investigate the individual concerned.

"This power will include appropriate safeguards and oversight arrangements."

Mr Cameron said if a legal challenge to royal prerogative powers was successful,new legislation would be immediately introduced to ensure Parliament, and not the courts, set the law.

Terrorism prevention and investigation measures (Tpims) will also be reinforced, Mr Cameron said, telling MPs: "The intelligence agencies and police believe they need stronger powers to impose further restrictions and the independent reviewer of counter-terror legislation, David Anderson, agrees.

"We will introduce new powers to add to our existing Tpims, including stronger locational constraints on suspects under Tpims, either through enhanced use of exclusion zones or through relocation powers."

Replying to the statement, Labour leader Ed Miliband branded the Government's move to get rid of so-called "internal exile" powers to relocate terror suspects in the UK a "mistake" and welcomed their reinstatement.

Mr Miliband welcomed plans to give police and border officers the power to seize passports but said Mr Cameron's proposals to exclude British nationals involved in terrorism abroad from entering the country were "unclear".

But the Opposition leader said he would be happy to engage in cross-party talks on the issue of excluding UK citizens from the country.

He said: "I welcome your commitment to make it easier for police and border authorities to seize the passports of those participating in the conflict and we will study and scrutinise your proposals.

"Let me say, on your discretionary powers on excluding British nationals from the country, it is unclear what you are proposing.

"I am happy to engage in cross-party conversations but can you give the House a bit more information at this stage about what your proposals might consist of?

"With regards to the most serious high-risk cases where convictions in the courts cannot be achieved, I welcome your recognition that the Independent reviewer on terrorism had made clear the inadequacies of Tpims.

"In particular, the inability to relocate suspects away from their communities.

"Relocation was indeed a central part of control orders and it was a mistake to get rid of them in the first place."

Mr Miliband also urged the Prime Minister to introduce a "mandatory and comprehensive" programme to deradicalise both terror suspects and those who have been "on the fringes" of extremism in Iraq and Syria.

The Labour leader criticised the Government for making the Prevent counter-terrorism strategy "overly focused" on the police response to terrorism and said there needed to be a focus on parents and communities.

He added: "As we tackle these domestic consequences of Isis, we will work with the Government to tackle the threat we face here at home.

"The events of this summer have underlined how turning our back on the complexities and instability of our world is not an option.

"But we must also show that Britain has learnt the lessons of our history with an approach based on genuine multilateralism. In responding in this way, the Government will have our full support."