Australia's Defence Minister John Faulkner on Wednesday announced plans to quit the cabinet, dealing a blow to new Prime Minister Julia Gillard as national elections loom.
The heavyweight senator said he would return to the back benches after the polls, but denied the move was prompted by last month's Labor party coup which dumped ex-leader Kevin Rudd, a close political ally.
"Inevitably some will suggest that the recent change in our party's leadership is responsible for my decision," he told reporters.
"I can't say strongly enough that any such speculation is just plain wrong."
Faulkner said he had always intended to step down after Labor's first term to encourage younger talent, adding that Gillard had persuaded him to contest his Senate seat in the elections later this year.
"Julia Gillard has my absolute support," he said.
"I was unstinting in my efforts to see Kevin Rudd elected prime minister three years ago and no one will work harder than me for the government's re-election under Julia's leadership."
Faulkner is the second senior cabinet member to announce his resignation since Gillard's sudden rise to power, after popular Finance Minister Lindsay Tanner said he would not contest the election.
The 56-year-old powerbroker became Rudd's defence minister in June last year, after his predecessor Joel Fitzgibbon stepped down following a series of scandals.
His announcement comes during rampant media speculation that Gillard is about to call elections after moving quickly to tackle the key issues of a controversial mining tax and immigration.
"I'm a little bit old-fashioned about these things," Faulkner said.
"I wasn't willing to be placed in a (difficult) position during the election campaign, if asked whether I would serve as defence minister in the government if the government were re-elected."
Gillard said Faulkner, who also served under ex-prime minister Paul Keating in the 1990s, had "a further contribution to make as a member of the parliament and member of the team", according to public broadcaster ABC.
Faulkner was a key member of the centre-left Rudd's campaign team for the 2007 elections, which he won by a landslide from long-time conservative leader John Howard.
He was also in Keating's cabinet in the 1990s, and was Senate leader of the opposition after 2001 elections.
Faulkner was famously caught unawares during last month's rapid leadership challenge when he admitted knowing nothing about the drama unfolding behind the scenes in Canberra.
"It might be on the ABC news, but it's also news to me," Faulkner said during a TV interview in the midst of the coup.
His unexpected resignation comes after Gillard laid the groundwork for the polls by defusing the tax row with the powerful mining industry and unveiling a tough new policy on asylum-seekers.