British nationals who fight in Iraq and Syria could have passports confiscated under tough new proposals.

David Cameron, UK prime minister, has outlined tough new measures to prevent British nationals fighting in Iraq and Syria from returning home.

A new counterterrorism bill would also prevent airlines that do not comply with Britain’s no-fly lists from landing on its territory.

Under the proposals, Britons thought to be heading abroad to fight could be prevented from leaving, while fighters returning from conflicts could be denied entry for two years, with an option to extend that, unless they agree to certain, strict, conditions.

Decisions would be made on the basis of what the proposal calls, "reasonable suspicion of involvement in terrorist activity".

Cameron unveiled the proposed measures in an address to Australia's parliament in Canberra on Friday.

He said "we will shortly be introducing our own counterterrorism bill in the United Kingdom: new powers for the police at ports to seize passports, to stop suspects travelling and to stop British nationals returning to the UK, unless they do so on our terms, new rules to prevent airlines that don't comply with our no-fly lists, or our security screening measures from landing in the UK".

Critics are concerned the new law could violate human rights, and compromise existing laws on immigration and citizenship, with the potential of leaving suspects stateless.

On Inside Story: Testing the boundaries between liberty and security?

Presenter: Mike Hanna

Guests:

Hannah Stuart - a research fellow at the Henry Jackson Society, specialising in anti-extremism policies in the UK.

Anjem Choudary- a Muslim social and political activist.

Margaret Gilmore - a senior associate fellow at the Royal United Services Institute (RUSI).