Total SA (TOT) said Friday 647 contract workers at its U.K. Lindsey oil refinery have had their contracts terminated after staging unofficial strike action this week.

The number of workers thought to be impacted by the decision to cut jobs, however, had been estimated by the Unite union at closer to 900.

Unofficial strike action started at the 200,000-barrel-a-day Lindsey oil refinery last week following a dispute with a subcontractor over 51 layoffs, with as many as 1,200 contract workers walking off the site. Total said production hasn't been impacted.

The dispute has sparked a number of unofficial strikes and protests at other energy facilities across the country.

Some 450 maintenance and construction contractors downed tools at Royal Dutch Shell's (RDSA) Stanlow refinery in Cheshire, northwest England, earlier Friday, following around 360 contract workers at two of RWE AG's (RWE.XE) U.K. power stations.

A number of workers at British Energy's Hinkley Point B nuclear power station also walked out earlier Friday, joined by around 150 contractors at E.ON AG's (EOAN.XE) Ratcliffe power plant.

Total said contract company Jacobs Engineering Group Inc. (JEC) had informed workers of the decision Thursday. Workers have until 1600 GMT on June 22 to reapply for their jobs.

-By Angela Henshall, Dow Jones Newswires; +44 (0)20 7842 9285; angela.henshall@dowjones.com