The latest unofficial one-day stoppage yesterday was triggered by existing shift rotation patterns on the site.

Erectors want to change the 11/3 and 10/4 rotation to a regular 10/4 arrangement.

The stoppage follows a developing pattern of industrial unrest among trades in recent weeks.

More than 300 scaffolders working at the Hinkley Point site are now planning a day a week on unofficial strike action after downing tools last Wednesday.

The scaffolders working for BYLOR are understood to be angry about pay rates and shift patterns on the site.

Around 125 mechanical and electrical workers under the MEH Alliance also staged an unofficial walk-out the week before that.

This was sparked by a decision by employers to cut travel allowances by 50%.

Since then, it is understood that the MEH Alliance contractors – Altrad, Balfour Beatty Bailey, Cavendish Nuclear and Doosan Babcock – have agreed to restore travel allowances.

Meanwhile, workers at a Hinkley Point supplier have just secured a pay boost worth up to 13% after seven weeks of action.

More than 150 platers, welders and sheet metal workers at Darchem Engineering, in Stockton-Upon-Tees, walked out in the strike action.

The pay deal will help workers in the cost-of-living crisis.

Andrew Blunt, GMB Organiser, said: “Workers have stood strong together for what they are worth.

“They were offered split deals, real terms pay cuts, and deals that would have delayed any 2024 discussions – leaving them further out of pocket. They rejected them.

“Together they have won a deal that will help them through the cost-of-living crisis.”