Home Affairs Minister Peter Dutton says a foiled terrorist attack in Melbourne proves federal parliament must quickly pass new laws allowing police to access encrypted messages.

Three men were charged with terrorism offences on Tuesday, with police saying the accused were using encrypted communications.

"The technology now has got ahead of where the law is," Mr Dutton told reporters in Sydney.

"We are finding ourselves in a particular black spot where the police are blind to the telecommunications across these messaging apps and it is unacceptable."

A Liberal-chaired parliamentary committee is examining the legislation which would require tech companies to hand over encrypted messages when authorities are investigating crimes.

"It's been delayed now within the committee process and we have to get it out of that process and into the parliament as quickly as possible," Mr Dutton said.

He also accused Labor leader Bill Shorten of being against the encryption laws, despite the opposition insisting no final position would be reached until the committee finished its review.

"Mr Shorten has been opposed to this legislation but he needs to review his position as well. We are in a position of vulnerability," the minister said.

The chances of passing the bill in final sitting fortnight appear slim, with the committee due to hold three more public hearings including one just two days before parliament rises for the year.

Mr Dutton said pedophiles were using encrypted messaging apps to direct acts of child sex abuse, while the Bourke Street terror attack was further proof authorities needed more power.

"At the moment we have pedophiles, we have people involved in terrorist planning, in criminal activity or otherwise, who are using encrypted messages," he said.