Royal Dutch Shell said on Wednesday it would start large-scale maintenance of its Pernis refinery in the Netherlands in mid-April, more than two weeks earlier than previously planned.
The maintenance would mean the 404,000 barrel per day refinery, Europe's largest, would be shut temporarily, it said.
The previous maintenance plan involved starting on 4 May and was expected to last through May and June.
Shell said it would be taking precautionary measures during the turnaround like working in small teams and keeping a safe distance between workers to prevent the spread of the new coronavirus.
It also said it had been able to almost halve the number of employees on site.