Gabon strike cuts oil output, shutters refinery -union

* Panic fuel buying hits capital Libreville

* Union says Total, Shell (LSE: RDSB.L - news) oil production affected

* Strike began on Monday night over jobs, benefits (Adds detail on production, reasons for the strike)

By Gerauds Obangome

LIBREVILLE, Dec 3 (Reuters) - Top international oil producers in Gabon were forced to cut output while Gabon's sole refinery was shuttered as more workers joined an industry-wide strike in the former French colony, union ONEP said on Thursday.

The former OPEC member pumps around 230,000 barrels of oil per day but is heavily reliant on imported fuel. Oil accounts for around 50 percent of Gabon's gross domestic product.

ONEP, which began the strike on Monday night, released a note late on Wednesday showing that output from Royal Dutch Shell had fallen by 80 percent as a result of the strike. Output from French major Total had also fallen at the Coucal field, it said.

A Shell spokesman confirmed that production was affected, without giving further details. Total said that output was down by around 10,000 barrels per day because the strike had hampered its ability to resume work at oilfields after maintenance.

Concern over fuel shortages has created long queues at service stations in the capital Libreville.

"Sogara (refinery) stopped production yesterday at about 1400 (local time)," said Sylvain Mayabi Bine, deputy secretary general at the union ONEP. The plant is the country's sole refinery, processing around 21,000 barrels per day.

An industry source in the oil hub Port-Gentil said the strike had disrupted supplies of jet fuel to the local airport.

According to ONEP, workers at the fuel distribution firm SGEPP were participating in the strike, although temporary staff had stepped in to help with deliveries.

ONEP declared the open-ended, industry-wide strike this week after weeks of talks with the government collapsed over jobs and benefits.

The union, which represents a majority of its more than 5,000 workers, has been demanding the reinstatement of some workers who were fired from oil companies, among other issues.

Gabon's President Ali Bongo on Wednesday met with Total CEO Patrick Pouyanne in Libreville, the Presidency said, without giving details of the discussion. (Additional reporting and writing by Emma Farge; editing by David Evans)