MOSCOW- Russian Urals oil loadings from Primorsk port were increased by 100,000 tonnes in December to 2.5 million tonnes after an extra cargo was added to the plan, three traders told Reuters on Monday.

That makes overall Urals loadings from Baltic ports in December 3.8 million tonnes including 1.3 million tonnes planned for loading from Ust-Luga port.

One loading position with small producers' resources was added to the plan for loading on Dec. 27-28, traders said. The cargo will be loaded by a trading firm Marsa and Glencore is a buyer, they added.

Marsa also has two other positions with small producers resources for loading from Primorsk on Dec. 26-27 and 28-29, according to the loading plan.

(Reporting by Olga Yagova, Gleb Gorodyankin, editing by Louise Heavens) ((Olga.Yagova@thomsonreuters.com;))