Chevron and BB Energy each made preliminary tanker bookings to bring a distillates cargo from the US Gulf to Europe, loading this week, shipping data showed on Tuesday.

Refining margins for diesel and gasoil delivered next year are wilting as concerns about a recession-driven drop in consumption replace earlier fears about a shortage in fuel availability caused by new maritime regulations.

Nigerian state oil firm NNPC issued award letters on Monday for highly sought-after contracts to exchange crude oil for imported fuel for one year, oil industry sources told Reuters.

A total of 15 groupings, including at least 34 companies, received award letters, according to four sources with knowledge of the deals.

The new contracts are expected to start with October-loading cargoes, they added.

The United Arab Emirates' state-run ADNOC, long viewed as one of the most conservative oil companies in the Middle East, plans an overhaul for its trading operations as it seeks to emulate the success of rival oil majors and bolster its regional influence.

Water levels along the Rhine river, a key waterway for transporting commodities and other products to inland locations from ARA, fell to 183 cm at the Kaub point, 10 cm lower than the previous day and their lowest since May 21.

Rising imports from the Middle East and Asia Pacific were weighing on margins, traders said.