Tokyo Gas said it had signed a 15-year deal in Sydney to take between 1.5 and 1.75 million tonnes per year of Pluto LNG from 2010. The contract has a five-year extension option.

Less than two months ago, Tokyo Gas also signed a 25-year deal to buy 1.2 million tonnes a year from Chevron Australia's share of the Gorgon LNG project. The company was also a founding customer with the Woodside-operated North West Shelf project.

Woodside has been fast-tracking the development of an onshore LNG development based on the the Pluto gas field, which was discovered only in April.

The field is officially estimated to contain 3 trillion cubic feet of gas. But to justify the cost of an LNG project, Pluto must contain substantially more gas or Woodside must be banking on tying the development at some stage with another field, such as the nearly Wheatstone discovery owned by Chevron.

Woodside aims to sell an initial 4 million tonnes per year of LNG from Pluto. A final investment decision is due in mid-2007.

More contracts with north Asian buyers are expected to be announced before the end of the year. The cost of the Pluto project will be more than $2 billion.

Tokyo Gas distributes city gas to more than 9.6 million customers in Tokyo. It is Japan's largest gas utility, accounting for more than 40% of total Japanese gas sales. The company bought about nine million tonnes of LNG in 2004-05 from suppliers around the world.