UK refinery Coryton has attracted more than 40 interested parties following the insolvency of its owner, Swiss refining group Petroplus, and some of them are very credible, its administrator said Thursday.

There have been over 40 expressions of interest from the speculative to the highly credible, Katherine Howbrook, a spokeswoman for PwC, said.

There have been a wide variety (of interested parties) including from major European oil companies to trading houses and companies from the Middle East and Russia.

The Coryton refinery, which can process 175,000 barrels of crude oil per day, has been in UK administration with PwC since January 24.

The administrator bought one cargo of crude Tuesday, allaying fears that a lack of supplies would force it to stop operations.

The plant is the most sophisticated of the company's refineries and is more profitable than others.

(Reporting by Simon Falush, editing by Jane Baird)