Up to 200 workers from both plants downed tools on Monday, Tuesday and yesterday, as well as last Thursday and Friday, as a show of sympathy with employees at Lindsey oil refinery.

The dispute came after one sub-contractor cut jobs, while another on the same site started hiring staff.

About 600 staff have already paid a high price after being sacked by the firm following the demonstrations as the row rages on.

A Drax site spokesman said workers didn't have any issues with the station and no electricity production was affected.

He added: "A number of contractors didn't come into work on those days. The dispute doesn't involve Drax – they're showing sympathy with fellow colleagues in Lincolnshire.

"Crucially, power generation at the site remains unaffected."

The spokesman didn't have an exact figure of how many rebels took strike action, but said it was "less than 200".

Action follows copycat protests involving Drax Power Station workers in February over a similar dispute at Lindsey.

On that occasion, about 150 staff staged 48-hour wildcat strikes at the awarding of contracts to non-UK employees.

Strikes were expected to continue until at least the end of the week.