UPDATE 1-Strike continues at two French nuclear plants

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PARIS, April 20 (Reuters) - Workers at France's nuclear power plants of Dampierre in central France and Chinon in southwestern France extended on Monday a strike which began on April 16, the CGT union said.

"Staff at Dampierre and Chinon voted to continue the action," a union spokesman told Reuters.

EDF said production was unaffected at Dampierre but the utility was not immediately able to say whether output had been curbed at the Chinon plant.

French energy workers voted on Friday to strike on April 21 and April 23 in an ongoing protest over salaries.

"We expect power capacity cuts to be similar to those observed on Thursday," the spokesman said.

A 24-hour strike by energy workers in France had cut about 6,000 megawatts (MW) of the country's power capacity.

This included a fall of 3,500 MW in nuclear power capacity, with the cuts affecting at least five out of France's 19 nuclear plants.

Unions are meeting with EDF managment on April 21 at 0700 GMT with the aim of boosting salaries by five percent and obtain a one-off bonus. (Reporting by Muriel Boselli and Mathilde Cru, Editing by Peter Blackburn)