UPDATE 1-Shell: Pulling workers due Fay; no output shut

HOUSTON, Aug 16 (Reuters) - Shell Oil Co (RDSa.L) said it was pulling 200 workers from the eastern Gulf of Mexico ahead of Tropical Storm Fay, but no offshore production was shut as of Saturday morning.

The workers are not essential to Shell's offshore operations, the company said in a statement.

The sixth cyclone of what experts predict will be an unusually busy Atlantic hurricane season, Fay was expected to be near hurricane strength when it approaches Cuba on Sunday and at hurricane strength over the Florida Keys and off Florida's west coast after that, U.S forecasters said.

Fay is the third storm of the 2008 Atlantic hurricane season to menace U.S. offshore oil and natural gas production, which provides 25 percent of U.S. oil output and 15 percent of U.S. natural gas production.

This year's Hurricane Dolly and Tropical Storm Edouard only temporarily shut fractions of offshore production and did not outweigh geopolitical factors or the U.S. economic outlook in determining crude oil and refined products prices.

U.S. Gulf producers fear a repeat of 2005 when hurricanes Katrina and Rita temporarily shut a quarter of U.S. oil and fuel production, sending prices to then-record highs.

As of 2 p.m. EDT (1800 GMT) Tropical Storm Fay was in the Caribbean Sea between Haiti and Cuba, according to the U.S. National Hurricane Center.

Shell Oil Co is the U.S. unit of Royal Dutch Shell Plc. (Reporting by Erwin Seba, editing by Patricia Zengerle)