Home Affairs Minister Peter Dutton has said encrypted messaging apps are allowing terrorists and criminals to communicate without police knowing.

Speaking in the wake of a foiled alleged terror plot in Melbourne this morning, Mr Dutton said the use of the apps, which include the popular WhatsApp, are blindsiding authorities.

Peter Dutton addressed the media this afternoon, in wake of an alleged foiled terror plot in Melbourne. (9NEWS)

“There is a significant problem in relation to the use of encryption messaging, this is a problem that a lot of Australians have heard about,” he said during a press conference this morning.

“Encryption is very important for us when we’re using internet banking and secure messaging, but the fact is at the moment we have pedophiles, we have people who are involved in terrorist planning, in criminal activity, who are using encrypted messaging.

“We have people now who are swapping messages using encrypted messaging apps, and police are blind to those messages.

“The police don’t have the ability to get across that technology, that is the significant issue.”

Mr Dutton said encrypted messaging apps are a security "black-spot". (AAP)

Mr Dutton urged for the intelligence committee within parliament to return their advice back to the parliament as soon as possible.

“We are in a position of vulnerability,” he said.

“This is legislation that the government needs to deal with urgently,” he said.

He added that there is a bill currently before parliament outlining suggesting safety mechanisms and privacy protections in place that would “allow police and ASIO to do their jobs”.