The move comes as refiners in Europe face overcapacity and global competition. Reuters cited the company spokesman Jan Maarten van der Steen as saying: "Now we have to look at all other options.
Currently, the company is negotiating with banks including HSBC regarding managing a potential sale.
Steen said the company has two options for the refinery which include could converting it into a storage terminal or closing it entirely."We are working on a new collective labour agreement."
Kuwait Petroleum intends to make a preliminary decision by spring 2015.
A union source said that the staff will be reduced to about 80 from around 350 if the refinery is turned into a terminal.
