PERTH, Australia--Chevron Corp. (CVX) and partners won the support of a key regulator Tuesday for a plan to expand the giant Gorgon gas export project in Western Australia state by eventually building a fourth processing unit.

The Chevron-led proposal--which would see Gorgon liquefied natural gas production capacity increase by roughly a third to 20 million tons annually--has been recommended for conditional approval, Western Australia's Environmental Protection Authority said in a statement.

The expansion plan, which also needs approval by state and Federal environment ministers, doesn't guarantee construction will go ahead. Developers of Australian energy projects have been scaling back or deferring plans following the plunge in world energy prices that have lowered returns on those investments.

Recently, Woodside Petroleum Ltd. (WPL.AU) and partners including Royal Dutch Shell PLC (RDSA.LN) and BP PLC (BP.LN) pushed back a final investment decision on their Browse gas-export project to mid-2016, from previous guidance of the second half of 2015.

Construction of Gorgon's US$54 billion first stage is more than 90% complete and the venture, which also counts Exxon Mobil Corp. (XOM) and Royal Dutch Shell as significant shareholders, is due to ship its first cargo of liquefied natural gas later this year.

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