David Cameron will make it easier for intelligence agencies to access information about airline passengers and announce measures to intensify cooperation with Turkey and Germany as the government moves to stem the flow of British-born jihadis travelling to and from Syria and Iraq.

As the king of Saudi Arabia warned that terror groups would attack Europe in the next month unless they were confronted with "power and speed", the prime minister will hold a final round of talks with Nick Clegg on Monday before outlining the package of measures to parliament.

The prime minister and his deputy have reached broad agreement on plans to make it easier to strip suspected jihadis of their passports in Britain and to improve the flow of data about airline passengers to the intelligence agencies.

But Clegg and Cameron will try to resolve differences on possible plans to impose a temporary ban on British-born jihadis returning to Britain and plans to tighten up terrorism prevention and investigation measures (Tpims), the successor to control orders.

The prime minister outlined plans to strengthen "information sharing" between European Union member states on airline passengers in a paper which he presented to EU leaders before their summit in Brussels at the weekend. Britain wants to persuade MEPs with concerns about civil liberties to drop their opposition to an EU directive which would allow countries to collect and share airline passenger name records in real time.

Before the summit, a government source said: "We think there should be urgent adoption of [the directive]. It is stuck in the European parliament at the moment. It would enable much more rapid sharing and monitoring of such information."

Signs of coalition tensions were highlighted when Paddy Ashdown and Sir Menzies Campbell, two former leaders of the Liberal Democrats, criticised Cameron's response on Friday to the decision by Joint Terrorism Analysis Centre (Jtac) to raise the terrorism threat level from substantial to severe. Cameron warned of "gaps in our armoury" as he spoke of a "generational struggle" that could see an Islamic State-led (Isis) caliphate stretch to the shores of the Mediterranean.

Lord Ashdown accused Cameron in an Observer article of a "kneejerk" response while Campbell warned that plans to impose a temporary ban on UK-born jihadis returning to Britain could infringe international law.

Campbell told The World This Weekend on BBC Radio 4: "That might well constitute illegality. To render citizens stateless is regarded as illegal in international law. To render them stateless temporarily, which seems to me to be the purpose of what has been proposed, can also be described as illegal. At the very least it is the kind of question that would be tested here in our own courts and perhaps also in the European court of human rights."

It is understood that Clegg and Cameron do not see their discussions as a coalition row because they both respect each other's record in speaking up on civil rights.

They also agree Britain must make improvements as it seeks to deal with the estimated 500 British citizens who have travelled to Syria and Iraq to fight for Isis.

A further 250 are believed to have returned to Britain. Many have travelled through Germany and Turkey, which explains plans to improve cooperation with the two countries.

But there are differences over plans to impose a temporary ban on returning jihadis. It is understood that the names of suspects could be added to a list, which would then be sent to friendly countries such as Germany and Turkey, who would be asked to prevent them entering the UK.

The discussions between Clegg and Cameron are focusing on the legal and practical aspects of the proposal.

Legal advice has suggested that it is possible to strip a UK citizen of their passport in Britain as a way of confining them to the UK. But the legal advice also suggests that if a UK citizen's passport is cancelled after they have left the UK they are still entitled to return home.

The discussions between Clegg and Cameron are focusing instead on proposals that would allow the authorities in the likes of Germany and Syria to prevent British-born jihadis boarding aircraft. They would then be taken in for further questioning, but would be re-admitted to Britain.

There is agreement between Cameron and Clegg on the need to improve the flow of airline passenger data to the intelligence agencies.

One problem is that some airlines do not release their passenger manifests until 30 minutes before flights leave. There will also be moves to share more passenger data. But this will involve stepping up negotiations with the European parliament, where plans to share passenger data have been challenged by MEPs concerned about civil liberties.

The two leaders have also yet to reach agreement on reforming terrorism prevention and investigation measures (Tpims) after David Anderson, the independent reviewer of terrorism legislation, called for a strengthening of "locational constraints" in his annual report in March. This could ban those subject to Tpims from some areas or to restore the power to relocate them to specific areas.

It is understood that their discussions are focusing on how any changes to Tpims would have to make clear that these would apply only in the most exceptional circumstances.Yvette Cooper, the shadow home secretary, called for the reintroduction of much tougher control orders. Cooper said: "Since Tpims were introduced, two terror suspects absconded – one in a black cab, one in a burka.

"While the relocation power was used in control orders nobody absconded and the courts consistently upheld them as proportionate and lawful.

"There are currently no Tpims in use because the experts have warned that the police and the security services do not believe they are effective enough to be worth using."

In his warning, King Abdullah of Saudi Arabia did not name any group but told foreign ambassadors on Friday that he was "certain that after a month they will reach Europe and, after another month, America", according to the Associated Press.

• This article was amended on 31 August. Turkey, not Syria, is regarded as a friendly country.