PASSENGERS at airports across Australia will be forced to undergo full-body scans or be banned from flying under new laws to be introduced into Federal Parliament this week.

In a radical $28 million security overhaul, the scanners will be installed at all international airports from July and follows trials at Sydney and Melbourne airports in August and September last year.

The Government is touting the scanning technology as the most advanced available in the world, with the equipment able to detect both metallic and non-metallic items beneath clothing.

It's also keen to allay concerns raised on travel online forums that passengers will appear nude on security screens as they did when similar scanners were introduced at US airports.

Despite being able to detect both metallic and non-metallic objects beneath clothing, the technology will show passengers on a screen as stick figures of neither sex. The system has approval from the Privacy Commission.

The images will be discarded after each passenger has been cleared.

The proposed Aviation Security Amendment (Screening) Bill 2012 will make it mandatory for any passenger selected to participate to have a body scan.

The "no scan, no fly" amendment closes a loophole in the legislation that lets passengers request a pat-down instead of passing through a metal detector.

Transport Minister Anthony Albanese said mandatory body scans were necessary to ensure the safety of airports.

"For this technology to work effectively, obviously there can't be an option to refuse screening," he said.

"I think the public understands that we live in a world where there are threats to our security and experience shows they want the peace of mind that comes with knowing government is doing all it can."