Anti-terror laws combat loopholes: Brandis

New anti-terrorism laws will ensure there are no loopholes for people who support terrorist activities, the federal attorney-general says.

Senator George Brandis says the laws, which he will introduce to parliament this week, will give authorities the power to track people of concern even if there is insufficient evidence to charge them with a criminal offence.

"The government wants to make sure that the police and also the intelligence agencies have all the power they need in all circumstances to deal with what has got to be acknowledged now by all sides of politics to be a very serious problem," he told the Nine Network on Monday.

He said Australia's existing anti-terrorism legislation, introduced by the Howard government in 2005, were "quite strong laws".

"But any prudent government reviews laws from time to time to make sure there are no loopholes, that there are no gaps," Senator Brandis said.

"That's what the prime minister asked me to do and the result of that exercise will be the two bills I'll be introducing into the parliament this week."