Deputy Opposition Leader Julie Bishop claimed yesterday that Prime Minister Kevin Rudd had been forced to remove Mr Fitzgibbon from the line of fire.

Mr Rudd said on Thursday that he had accepted Mr Fitzgibbon's resignation after it emerged the then Defence Minister's staff had organised and attended meetings between Defence health officials and the medical benefits fund NIB, which his brother heads.

Mr Fitzgibbon resigned an hour before he would have faced Opposition questions in Parliament.

''What the Prime Minister has done is remove Joel Fitzgibbon from the line of fire,'' Ms Bishop said yesterday.

''We certainly had more questions, more lines of inquiry of him over his behaviour going back months. This is a minister who has very questionable behavioural issues ... so there were many unanswered questions about his honesty, his competence, his judgment.''

Ms Bishop went on to argue that the ministerial reshuffle prompted by Mr Fitzgibbon's resignation rewarded those in the Labor Party who supported Mr Rudd to win the Labor leadership in 2006.

More on the opposition's claims in today's Canberra Times