Chevron Corp started evacuating contractor workers from its Gorgon liquefied natural gas (LNG) facility on Saturday, shortly after staff went on strike at two major projects in Australia, a union alliance said.

"Chevron chartered a special flight this morning to Barrow Island to evacuate 50 blue and white collar contract crew off the Gorgon Project," union coalition Offshore Alliance said in a Facebook post.

Chevron did not immediately respond to a Reuters request for comment outside of business hours.

The two sides are at odds over issues including pay, job security, rosters and rules around overtime and transfers between Chevron facilities.

Workers at Chevron's LNG projects in Australia started strike action on Friday after talks broke down, potentially disrupting output from facilities that account for over 5% of global supply.

No further talks were scheduled between the unions and the U.S. energy major, according to the website of the Fair Work Commission, Australia's industrial umpire, which had mediated five days of negotiations.

Australia is the world's biggest LNG exporter and its main buyers are in Asia.

The dispute over wages and conditions at Chevron's Gorgon and Wheatstone operations has supported British and European gas prices, as traders anticipate lower Australian supplies would intensify competition from other sources.

(Reporting by Jyoti Narayan in Bengaluru; Editing by Tomasz Janowski and Mike Harrison)