A labor strike has broken out at a big refinery owned by US oil giant Chevron.

A total of 500 workers laid down work Monday at the refinery, located in Richmond, California, reports Wall Street Journal.

The workers' contracts expired on Feb. 1 this year, and parties have since tried to draft a new wage settlement. However, negotiations are at an impasse, say workers in union United Steelworkers, according to the media.

Employment conditions, workers say, are unacceptable, as they demand a more fair contract that reflects efforts rendered during the Covid-19 pandemic of the last few years.

“USW members continued to report for work throughout the pandemic so our nation could meet its energy needs,” says Mike Smith, chair of the United Steelworkers’ National Oil Bargaining Program, to the WSJ:

“They deserve a fair contract that reflects their sacrifice.”

3,000 workers are employed at the refinery, according to Chevron, which in January booked net earnings of USD 5.1bn for fiscal 2021.

“We have negotiated in good faith for months, reaching two tentative agreements that were rejected by the union, and we are ready to continue discussions with USW so we can reach an equitable agreement,” Chevron says in a statement.

The oil company says its contract offer is both competitive and fair.

The strike comes as energy prices including oil are rising dramatically.

A barrel of US benchmark crude West Texas Intermediate trades for USD 114 Tuesday after rising by 1.9 percent since Monday.

Chevron stock is up 0.2 percent in pre-market trading.

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