Workers at the troubled Coryton oil refinery in Essex are going back into work, as news broke that the plant is now in administration.

Union Unite said staff would work through the night to get the plant back up to speed, easing fears of an imminent fuel crisis for the south east of the country.

Unite regional officer Russ Ball said: “Now that Coryton is in administration we expect normal operations to resume shortly, while PricewaterhouseCoopers get on with the job of securing a future for the refinery. The workforce is cautiously optimistic.

“They are prepared to work night shifts to ease the backlog and get things back to normal as quickly as possible.”

The plant’s owners, Swiss firm Petroplus, closed the refinery earlier this week after it defaulted on $1.75 billion of debt.

PwC, the Petroplus group’s administrators said the company had suffered as a result of “low refining margins and high restructuring costs.”