Nathan Rees confirmed as new NSW premier

Labor frontbencher Nathan Rees has been endorsed as the new premier of New South Wales following the dramatic resignation of Morris Iemma earlier today.

Mr Rees is currently the Minister for Water and Emergency Services and was widely tipped to put his hand up as a non-factional premier. His selection has emerged from a full Caucus meeting at State Parliament in Sydney.

"Morris Iemma resigned as Premier today and I nominated for the vacancy and I was elected with unanimous support of the full Labor Caucus," Mr Rees said.

He says he expects to be sworn in as premier this afternoon.

Mr Iemma resigned this morning, shortly after sacking his colourful treasurer, Michael Costa.

It is understood Mr Iemma gave a meeting of the Right faction an ultimatum and they refused to accept it. He walked out without saying a word.

Labor heavyweight John Della Bosca confirmed Mr Iemma's resignation.

It follows a tumultuous series of events that began with the Government's failure to privatise the state's electricity sector last month.

The Government's position was further weakened by the resignation of Deputy Premier John Watkins, who retired on Wednesday to spend more time with his family and take up a position with Alzheimer's Australia.

Former education minister Carmel Tebbutt was yesterday unanimously endorsed to take over as deputy by the Left faction during a meeting at State Parliament.

She will be formally endorsed this afternoon but it is not yet clear who else will make up the new-look Cabinet.

Some of Labor's Caucus appeared shell-shocked as they emerged from the partyroom meeting at State Parliament.

But Labor MP Linda Burney says the Caucus has rallied behind Mr Rees and Ms Tebbutt.

"We had two fine speeches from two fine men, we've got two new leaders and our job now is to get behind them, and that's absolutely what's happening," she said.

Fellow MP Michael Daley believes the changes offer the party new hope.

"The election in 2011, well you can say with the new leadership of Nathan Rees and Carmel Tebbutt that it's game on," he said.

Mr Daley says Mr Iemma was not tapped on the shoulder and that it was his decision to resign.

Tumultuous morning

News that Mr Iemma was gone came in the wake of a press conference by Mr Costa, who said he did not consider that he had been sacked until the decision was ratified by a Caucus meeting.

Earlier Mr Costa used his press conference to confirm that Mr Iemma had dumped him but suggested that he remained treasurer until the Caucus confirmed his sacking.

"I was advised by the Premier that he desired that I not be part of his ticket in the forthcoming reshuffle," Mr Costa said at his press call.

"I respect his right to do that."

Mr Costa is deeply unpopular with the public and with many of his own colleagues but he signalled that he was not prepared to go without a fight.

And typical of his style, he used his news conference to point the finger.

He accused his colleagues of lacking the "political courage" to make the hard decisions such as slashing big spending projects in rail and in health.

He also told the media that he was not prepared to stay on when the Iemma Government's approach risked New South Wales Triple-A credit rating.

"The job I'm interested in is the treasurer's job," he said.

"I'm interested in doing the mini-budget, but I am not prepared for political expediency to present a mini-budget that I know will threaten the triple-A credit rating.

"If you want me as treasurer you have to cop a mini-budget that will deliver a triple-A credit rating."

The Government faces an unwanted by-election in the state seat of Ryde, after one of its most competent performers, John Watkins, quit politics earlier this week, sparking manoevres around the necessary ministerial reshuffle.