CANBERRA (AFP) - Prime Minister David Cameron on Friday outlined plans to seize passports from radicalised Britons and stop them returning from fighting overseas, while proposing landing bans on airlines that fail to comply with London's no-fly lists.
"We will shortly be introducing our own new Counter-Terrorism Bill in the UK," he said in speech to Australia's parliament in Canberra before he travels to the G20 leaders' summit in Brisbane this weekend.
"New powers for 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 security screening measures from landing in the UK."
British media reports said the legislation, to be tabled in parliament this month, would block individuals from returning from Syria and Iraq to the UK for at least two years unless they comply with strict measures.
These could include being escorted back to Britain and then facing prosecution, bail-style reporting conditions and deradicalisation courses.
Border guards and airport police would also be given new powers to seize passports from those they suspect of planning to travel abroad for terrorism, the reports said.
Some 500 British extremists are estimated to be fighting in the two countries, both of which are facing a major offensive from the Islamic State in Iraq and Syria (ISIS) militant group.
Britain raised its terror threat risk level to "severe" in September - meaning an attack is thought "highly likely" - due to fears over the situation in Iraq and Syria.
Mr Cameron said that as well as handling the extremist threat, the root cause must also be dealt with. "And let's be frank. It's not poverty, though of course our nations are united in tackling deprivation wherever it exists," he said.
"It's not exclusion from the mainstream. Of course we have more to do, but we are both successful multicultural democracies where opportunities abound.
"And it's not foreign policy.
"No, the root cause of the challenge we face is the extremist narrative. So we must confront this extremism in all its forms.
"We must ban extremist preachers from our countries. We must root out extremism from our schools, universities and prisons.
"As we do so we must work with the overwhelming majority of Muslims who abhor the twisted narrative that has seduced some of our people."