Australia has announced new draft legislation which aims to better protect children from sexual abuse. 

Foreign Minister Julie Bishop said legislation proposed last week would allow the government to seize the passports of 20,000 pedophiles on the national child sex offender register. 

The aim is to crackdown on "sex tourism" and prevent sex offenders from taking trips to parts of the Asia-Pacific to abuse children. 

“The new laws will prohibit registered child sex offenders from leaving Australia or holding Australian passports,” Bishop said.

But University of New South Wales Law professor Annie Cossins says the government could face legal challenges, adding that not all convicted sex offenders pose a risk of re-offending. 

“As long as people have a right to have a passport why should that passport be taken away, especially for someone who has served a sentence and are out in the community?” said Cossins.  

Under the plan, more than 3,000 serious offenders would be banned from travel for life. The draft legislation will be considered by parliament later in the year.