CEFC has grown in a few years from a niche fuel trader into a diversified conglomerate with operations across the globe and more than 30,000 employees. However, it has had to start a fire sale of its assets as creditors scramble to collect debts following an investigation into its chief.

CEFC had initially agreed to buy 14.2 percent of Rosneft from Qatar and trading firm Glencore in 2017. Rosneft has also pledged to supply CEFC with 61 million tonnes of oil over five years starting on Jan. 1, 2018.

However, after the deal to buy a stake in Rosneft failed after CEFC's founder and chairman Ye Jianming was taken in for questioning and investigated by Chinese authorities for suspected economic crimes, traders had wondered whether the oil supply contract had changed hands.

In a regulatory filing on Tuesday, Rosneft said its board would consider on Jan. 25 a deal transferring obligations from CEFC China Energy Co Ltd (China) to CEFC Shanghai International Group (Singapore) Pte Ltd.

CEFC Shanghai is a CEFC trading arm that receives crude oil supplies from Rosneft and trades them further. A source at Rosneft said the move amounted to switching business to the Singapore arm, "which is carrying out operational activity".

Sources familiar with the matter said CEFC would take eight cargoes of ESPO Blend crude oil and two cargoes of Urals crude in March from Rosneft, indicating no change in volumes for 2019 so far.

CEFC did not immediately reply to a Reuters emailed request for comment.

(Reporting by Vladimir Soldatkin in Moscow and Florence Tan in Singapore; Additional reporting by Olga Yagova in Moscow; Editing by Katya Golubkova and Dale Hudson)