SYDNEY, May 28 (Reuters) - Australia approved on

Wednesday Woodside Energy's request to extend the life

of its North West Shelf gas plant until 2070, after a six-year

review process dogged by delays, appeals and backlash from green

groups.

The North West Shelf facility, located on the Burrup

Peninsula in Western Australia, is the country's oldest and

largest liquefied natural gas plant and a key supplier to Asian

markets.

Environment Minister Murray Watt said in a statement the

decision to approve the extension of the project would be

subject to strict conditions "particularly relating to the

impact of air emissions levels from the operation".

Woodside shares were trading higher through the day but

jumped after the announcement to be up 4% in the afternoon.

The project's existing approval was set to expire in 2030.

Woodside's extension application, lodged in 2018, had been

caught up in state and federal assessment processes due to

competing concerns over energy security and its environmental

impact.

The extension lays the groundwork for Woodside, Australia's

top gas producer, to bring new gas fields online to feed the LNG

plant and is expected to generate up to 4.3 billion metric tons

of carbon emissions over its lifetime.

The Western Australia state government cleared the project

in December after considering nearly 800 appeals launched by

activists. The federal government twice delayed making a call in

the lead up to the May general election.

With the North West Shelf's original offshore gas fields in

decline, the decades-long extension opens the door for Woodside

to develop its long dormant Browse offshore project to supply

gas to the Karratha plant.

Woodside's partners in the North West Shelf venture are

units of BP, Chevron ( CVX ), Shell, Japan's

Mitsui & Co ( MITSF ) and Mitsubishi Corp ( MSBHF ) and China's

CNOOC.