Citizenship bill gets a legal tweak

The federal government has tweaked controversial citizenship-stripping draft laws to head-off the possibility of a High Court challenge.

The legislation to revoke passports from dual national terrorism suspects was due to pass parliament's lower house this week but was delayed after the government made a last-minute change on Wednesday.

There were concerns the legislation was not constitutionally sound, with Labor warning it would not be held responsible in supporting the laws if they were challenged in the nation's highest court.

Immigration Minister Peter Dutton on Thursday said a technical change was being made to the bill following advice from the solicitor-general.

The government had taken steps to avoid the risk of a High Court challenge, which he said was "always a possibility".

"We have a stronger bill to defend," Mr Dutton told reporters in Canberra.

Labor said it will look carefully at the changes, criticising how they had been "sprung" on the opposition.

"We will work through that with them, we will try and understand what they are saying and doing," Opposition Leader Bill Shorten said.

Debate on the bill will be postponed until next week.

That gives the government just a few days to pass it through both houses of parliament ahead of the long summer break.

HOW DUAL NATIONALS WOULD LOSE THEIR CITIZENSHIP:

* If they engage in terrorist acts, provide or receive training in preparation for a terrorist act, direct activities of a terrorist organisation, recruit or finance terrorists or terrorism.

* If they fight in the service of a declared terrorist group - automatic loss.

* If convicted of a terrorism offence and sentenced to at least six years in jail.

* If they've been convicted of terrorism in the previous decade - retrospective measures allowing citizenship to be revoked for convicted terrorists in jail such as Abdul Benbrika.