The company finalised the contract with several traders to sell diesel with sulphur content of 10 ppm at a premium of $1.40 a barrel to Middle East quotes, they said.

This compares with a premium of $1.30 a barrel achieved for a January to December 2017 diesel contract it negotiated late last year, they said.

But this is far lower than a July 2016 to June 2017 diesel term contract, one of them said, though price details of that contract were not immediately available.

"Our July 2017 to June 2018 diesel term contract is in the process of being renewed, with no change in volumes," an ADNOC spokesman told Reuters.

ADNOC had in May sealed its July 2017 to June 2018 jet fuel term contract at a premium at 75 cents a barrel above benchmark Middle East quotes, but delayed its diesel term talks.