Julia Gillard remains as Prime Minister and Labor leader this evening after an expected Kevin Rudd challenge failed to materialise during another extraordinary day in Canberra.
Senior Labor minister Simon Crean triggered the remarkable chain of events earlier in the day after he asked the Prime Minister to call a leadership spill, when he said former Prime Minister Rudd had no option but to run.
Ms Gillard then announced at question time, which commenced at 2pm, there would be a ballot for the leader and deputy leader positions at 4.30pm, saying 'take your best shot'.
There followed a feverish couple of hours of speculation, focusing on whether or not Mr Rudd would actually run.
But Mr Rudd appeared before the cameras just 10 minutes before the expected vote to reveal he would not stand.
That left Ms Gillard as the only candidate for the leadership ballot - and her party in turmoil.
Opposition Leader Tony Abbott also failed to gain the absolute majority necessary to force a suspension of standing orders to debate a motion of no confidence in the government, just to add to the drama.
Mr Crean had 'pulled the trigger' on leadership speculation, saying it needs to be sorted today, so the party can move on.
However, key independents Tony Windsor and Rob Oakeshott have repeatedly warned their support for the Labor government is dependent on Ms Gillard continuing as Prime Minister.
Earlier this week, Mr Windsor warned a change at the top could see Australians heading to an early poll.
Ms Gillard has faced months of damaging leadership speculation, with polls repeatedly showing the ALP would face a landslide election loss under her leadership.
Mr Rudd, who failed in a leadership bid in February last year, has repeatedly said he would not challenge for the Labor leadership, but left the door open to be drafted by his fellow MPs.
HOW THE DAY UNFOLDED
6.45pm Only one person each nominated for the positions of leader and deputy leader of the parliamentary Labor party.
Julia Gillard and Wayne Swan have been re-elected unopposed to their positions.
6.30pm Kevin Rudd has announced he will not run for the leadership of the parliamentary Labor party.
Mr Rudd said he made a commitment not to challenge without the overwhelming support of the party - something he does not yet have.
"I made a commitment I would not challenge. While others take those commitments lightly, I do not", he said.
A ballot will still be held for the deputy leadership of the party, Simon Crean and Wayne Swan are expected to stand.
5.55pm Still no word from Kevin Rudd on whether he intends to throw his hat into the ring in this afternoon's leadership spill.
A delegation of Rudd backers has reportedly been to see the former PM to urge him to run.
5.21pm The number crunching has begun ahead of this afternoon's leadership spill.
Treasurer Wayne Swan has tweeted his support for the PM, "@JuliaGillard is as tough as they make them- she'll win today & on 14 Sept because she's got the reforms for the future"
Julia Owens and Kate Lundy have both also used social media to express support in the PM, while recently demoted MP Justine Elliot says she'll 'definitely' vote for Kevin Rudd.
4.42pm Opposition Leader Tony Abbott has failed to gain the absolute majority necessary to force a suspension of standing orders to debate a motion of no confidence in the government.
The PM lost the vote 73 - 71, but at least 76 votes (more than half of the House of Representatives) are required to suspend standing orders.
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4.35pm Prime Minister Julia Gillard has defended herself and her government after Opposition Leader Tony Abbott called a motion of no confidence in her government.
"Day after day we have made the right decisions", Ms Gillard told parliament, "It is this government that has outlined a roadmap to [the] future of prosperity".
The Prime Minister has also pointed to her efforts on education reform, the National Disability Insurance Scheme and 'sharing the benefits of the mining boom', as reasons to retain confidence in her government.
"We will fight and fight and fight the opposition leader's campaign to take hope away from the Australian people", she said.
4.10pm Tony Abbott has suspended standing orders in question time to move a motion of no confidence in the government.
"This is a government which has lost its way. Not a good government which has lost its way - a very poor government which has lost its way", a confident looking Mr Abbott told parliament.
"For you party's good, you should go. You should go.", he said.
4pm The Prime Minister has opened question time by confirming there will be a spill for the leadership of the federal parliamentary Labor party at 4.30pm AEDT this afternoon.
The PM concluded her opening remarks to question time by inviting the opposition to 'take its best shot'.
Simon Crean, the senior minister who instigated the leadership spill, is not present in question time, after the PM confirmed she had sacked him as a minister.
3.30pm Senior Labor minister Simon Crean has asked the PM to call a leadership spill, and says Kevin Rudd has no option but to run.
Mr Crean has 'pulled the trigger' on leadership speculation, saying it needs to be sorted today, so the party can move on.
"Something must be done to resolve the issue once and for all", Mr Crean said, confirming he would run for the deputy leadership of the party.
"Kevin Rudd has no option, in my view, other than to stand for the leadership", he said.
"I wouldn't be doing this if I didn't believe there was the mood and the need for change in the party", Mr Crean said when asked if Mr Rudd had the numbers to be successful.
Mr Crean said he did not expect the Prime Minister to agree to a spill, but urged caucus to use other mechanisms to force a vote.
Key independents Tony Windsor and Rob Oakeshott have repeatedly warned their support for the Labor government is dependent on Ms Gillard continuing as Prime Minister.