PARIS (Reuters) - ExxonMobil may need to suspend production at its Gravenchon refinery in northern France if striking workers continue to block access to the site, the oil major said on Tuesday.

The refinery accounts for about 20% of France's refining capacity, the company's website showed.

Blockades since Friday have prevented deliveries of goods and materials needed to maintain refinery operations, it said in an emailed statement.

A small group of workers called a strike last month after the company said it would shut down the refinery's steam cracker and close chemical production this year.

The site has lost more than 500 million euros ($535.55 million) since 2018 and remains uncompetitive, Exxon said.

Another strike was called on Friday that shut some of the chemical manufacturing units, including the steam cracker.

A "limited number of strikers" are still blocking access, Exxon said. "If this continues, we may have no choice but to suspend production from the refinery."

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