After more than a year of delays, Woodside's $14.9 billion Pluto project in Western Australia is finally up and running, with first production of liquefied natural gas expected within weeks.

Woodside chief executive Peter Coleman hailed the achievement of ready for start-up status as an important milestone as first gas entered the processing train late yesterday.

"This milestone is a credit to all those involved in the construction of Pluto, which proudly takes its place as Australia's third LNG project," Mr Coleman said in a statement to the Australian Securities Exchange.

"While the achievement of ready for start-up is a significant moment, our operations team remains focused on the path to steady-state production," he said. "Maintaining our focus on safety and integrity is a priority through this process."

The Pluto LNG project is expected to contribute 17 to 21 million barrels of oil equivalent to Woodside's 2012 production.

It will add to Australia's roughly 20 million tonnes per year of output from the Woodside-operated North West Shelf venture and ConocoPhillips' Darwin plant.

Another seven LNG projects are under development in Australia.

Mr Coleman, who took over from Don Voelte as Woodside chief in May last year, increased the budget for Pluto to $14.9 billion from an original estimate of $11.2 billion. It was the third time Woodside had lifted the budget for Pluto, making it the most expensive LNG plant in the world in terms of dollars per unit of capacity, according to some in the market.

One of Mr Coleman's first tasks in the new role was to announce another six-month delay in the start-up of the initial Pluto project, then due in August. Mr Voelte had held up Pluto as the fastest LNG project to go from discovery to start-up.

Woodside last month posted a 4.3 per cent dip in full-year profit to $US1.507 billion, weighed down by costs for the late delivery of the Pluto project, and higher costs for exploration, financing and taxes.

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