Now it seems the Prime Minister's inclination for wearing RM Williams boots to Parliament and other official events has crossed the floor.

Elastic-sided boots have been spotted on several prominent Liberal frontbenchers in recent weeks, including Malcolm Turnbull and Tony Abbott.

Abbott confessed to The Diary last week that he was a recent convert to the parochial trend after noticing they had of late become "quite the fashion item on the front bench".

Rudd famously wore the boots to meet Barack Obama earlier this year, attracting bemused comments from the US President and howls of derision from the British press when he later wore them in London.

Abbott, however, denied the boots-to-work trend originated with Rudd.

"Malcolm has worn them for much longer than I have," he said, adding that Peter Costello was another early adopter.

Costello picked up his first pair in 1997 - funnily enough on a trip to Queensland - and wore them at weekends before taking the cue from staff in his Canberra office and his National Party colleagues.

"If you looked down the front bench at question time it illustrated Coalition unity to see Liberals and Nats decked out in the same attire," Costello told The Diary.