Mr Rudd made the claim on Friday at a Canberra Writers Festival event while promoting his book, The PM Years.

The ALP has launched an independent review of what went wrong in the campaign, which saw Scott Morrison's coalition team returned to office on May 18.

Mr Rudd said he had campaigned in a dozen seats and concluded the key reasons for Labor losing were Mr Shorten's personal unpopularity, a too-complex policy offering and media bias.

"I think every candidate was (picking up the negative feedback about Mr Shorten)," he said.

Having changed the party rules around leadership spills in 2013, Mr Rudd said some Labor MPs during the 2019 campaign had raised with him whether leadership change was needed.

"Some of the caucus colleagues said to me: 'Bugger you, Kevin, for bringing in the rule'," he said.

"From time to time they were thinking about (changing leader).

"That's where you require senior leadership in the party, after a certain period of time, to say to the leader we should think this through."

He declined to say whether leadership change would have helped the party win the election.

Asked whether controversial policies on franking credit changes and winding back negative gearing concessions should be retained he said: "I just think that's nuts, absolutely nuts."

Australian Associated Press