BEIJING (Reuters) - Russia shipped record volumes of crude oil to China in October as independent refiners continued to fill import quotas, while Iranian oil shipments fell on uncertainty over Washington’s imposition of sanctions on Tehran, data showed on Monday.

FILE PHOTO: Smoke billows from a fire at oil refinery, owned by Russian oil producer Gazprom Neft, in Moscow, Russia, November 17, 2018. REUTERS/Tatyana Makeyeva

China’s imports from top supplier Russia jumped 58 percent from a year earlier to 7.347 million tonnes, according to the General Administration of Customs data, marking the highest ever and equivalent to about 1.73 million barrels per day (bpd).

For the first 10 months, Russian imports were at 57.91 million tonnes, or 1.39 million bpd, up 16.6 percent.

Chinese customs last month began updating an online database with commodity imports by country of origin, replacing a service that had until March only been available to clients. Percentage changes with year-earlier figures were calculated by Reuters.

China’s crude import demand hit an all-time high in October and is expected to stay strong to year-end as independent refiners snap up cargoes to use up their import quotas.

The strong demand from China’s so-called “teapot” refiners has helped to push spot premiums for popular grades such as Russian ESPO Blend and Oman crude to their highest in more than four years.

Iranian shipments, however, tumbled 64 percent in October from the year-ago month to 1.0496 million tonnes, about 247,160 bpd, ahead of U.S. sanctions that came into effect on Nov. 4.

Month-on-month, imports from Iran in October marked their third fall in a row as China’s state oil firms came under growing pressure to scale back purchases ahead of the sanctions.

For the January-October period, imports from Iran fell 3.4 percent from 2017 to 25.54 million tonnes, or 613,300 bpd.

China is one of eight countries that have been granted a waiver to continue buying some crude oil from Iran. The world’s largest energy consumer is allowed to buy 360,000 bpd of oil from the Islamic Republic for at least 180 days from the imposition of sanctions, Reuters reported.

Saudi Arabia’s shipments last month were 4.77 million tonnes, or 1.12 million bpd, up 3.4 percent from October 2017.

Imports for the first 10 months from the top producer in the Organization of the Petroleum Exporting Countries (OPEC) inched up 0.2 percent to 43.2 million tonnes, or 1.04 million bpd.

A search in the database for U.S.-sourced crude oil imports yielded no results.

Chinese firms stopped importing U.S. crude oil around August and September due to a growing trade spat between Washington and Beijing.

The suspension lasted until November when a cargo of 140,000 tonnes was discharged to a Chinese port.