Former prime minister Kevin Rudd repeatedly pressed ex-Labor leader Bill Shorten to launch a royal commission into News Corp Australia in the lead up to last year's federal election.

Mr Rudd, who later that year publicly called for a royal commission into the ownership and operation of the media, was particularly angered by an election campaign front page story in the Daily Telegraph which accused Mr Shorten of lying about the life story of his dead mother Ann.

"Gidday," Mr Rudd wrote to Mr Shorten on May 8 according to an account in Samantha Maiden's new book Party Animals to be released this week. "Don’t let the News Corp f---ers get you down. They massively overreached today."