The federal opposition is demanding to see a transcript of the telephone conversation between the two leaders.

"There is nothing normal about this - that's the point to be made here - we're talking about a leader to leader request," deputy opposition leader Richard Marles told the Nine Network on Friday.

"If there are investigations that our agencies are being asked to undertake by the FBI or some other agency in America, fair enough, there's a whole lot of protocols that apply in terms of getting those investigations open.

"But if in fact what's gone on here is the president has asked for a favour from his mate and all that Scott Morrison has said is 'Yeah, no worries mate, we will get straight on to it' then we need to know."

Home Affairs Minister Peter Dutton argues there was nothing remarkable about the request.

"Obviously if the prime minister gets a call from the president of the United States, he says that his attorney-general is undertaking an investigation, could we cooperate, well, of course we would," Mr Dutton said.

"So I know there's a lot of hype and a lot of over-egged enthusiasm by some on the other side, but I think the prime minister has done the right thing here and we will work with the United States."

He said it would be unusual to publish a transcript of the conversation.

Mr Morrison agreed to help the US president with a controversial inquiry into the FBI during a phone conversation last month.

The inquiry is widely seen as a partisan attempt by the Trump administration to discredit an earlier investigation into Russian interference in the 2016 US election.

The initial probe was sparked by a tip-off from former Australian diplomat Alexander Downer.

Australian Associated Press