Foreign Minister Julie Bishop believes Kevin Rudd is qualified for a top United Nations job, despite apprehension from some within the coalition.
Cabinet secretary Arthur Sinodinos admitted the prospect "grates" with some of his colleagues, with federal cabinet yet to decide on supporting Mr Rudd's bid for the secretary-general post.
"I believe that as the other candidates are former leaders, former prime ministers, former foreign ministers of their country, then he is qualified to be a candidate," Ms Bishop told the ABC.
Opposition foreign affairs spokeswoman Penny Wong said some coalition MPs who have questioned Mr Rudd's suitability for the role should consider the national interest.
"Sometimes nation is more important than party," she told ABC radio.
