SINGAPORE, Nov 16 (Reuters) - Global independent tank storage company Vopak is introducing a new contractual clause that requires customers to provide a certificate of origin for oil stored at its terminals, four industry sources told Reuters.

The move comes ahead of European Union sanctions on Russian crude oil and oil product imports that will take effect on Dec. 5 and Feb. 5, respectively.

The clause, to be added when customers renew their storage contracts, will apply to crude oil and refined products placed in Vopak storage tanks, the sources told Reuters.

Customers under earlier contractual terms are not affected for now, they said.

Vopak did not comment directly on implementation of the new clause. A company spokesperson said in an email that Vopak is monitoring the situation and "is fully committed to adhere to relevant sanctions laws and regulations."

More Russian barrels are expected to flow to Asia and the Middle East as further sanctions from the West shake up international oil trades.

Vopak has 73 storage terminals globally, with storage capacities totalling 36.2 million cubic meters, data from its website showed.

Regarding the measures to be taken against Russian oil shipments, Chief Executive Officer Dick Richelle said earlier this year Vopak had a process to track any sanctioned product that would potentially enter its terminals, as it has previously experienced similar actions in other parts of the world. (Reporting by Jeslyn Lerh; Additional reporting by Juliette Portala; Editing by Florence Tan and Tom Hogue)