SINGAPORE  - Kuwait Petroleum Corp has offered heavy crude for loading in December via a spot tender, according to trade sources and the tender document, as it sells excess oil that the Al-Zour refinery is unable to process.

The producer offered 500,000 barrels of Kuwait Heavy Crude for loading on December 6 to December 7 and the same volume of Eocene crude for loading on December 8 to December 9.

The tender will close on Wednesday with bids valid until Thursday. The offer brings KPC's total volume of heavy crude spot sales to 3.9 million barrels. On October 21, its affiliate, Kuwait Integrated Petroleum Industries Company, shut down parts of a 615,000-barrel-per-day Al-Zour refinery due to a fire.

The refiner has attempted to bring back online this week some of the atmospheric residue desulfurization (ARDS) units and plans to restart in the first half of December one of its three crude distillation units (CDUs) affected by the fire, two trade sources said.

KPC did not immediately respond to a request for comment.

(Reporting by Florence Tan, Trixie Yap and Siyi Liu; Editing by Christian Schmollinger)