Oil flat-lined Thursday as the upheaval in Ukraine continued to cancel out a big increase in U.S. oil supplies.

Benchmark U.S. crude for May delivery was up 1 cent at $103.77 a barrel at 0910 GMT in electronic trading on the New York Mercantile Exchange. The contract rose 1 cent Wednesday to $103.76. There is no oil trading on Good Friday, one of only three days a year in which oil is not traded either electronically or through open outcry.

Oil trading was hemmed in Thursday by opposing influences.

Tensions remained over Ukraine, where po-Russian militants clashed with Ukrainian forces in the country's east as authorities try to reassert control over a region where some are pushing to secede and join Russia.

Officials from the U.S., Russia, Ukraine and the European Union are set to meet in Geneva on Thursday for negotiations aimed at persuading Russia to back off in Ukraine following its annexation of Crimea.

Traders worry that Russia's actions could be met with sanctions that disrupt exports of the country's oil and gas. But that upward impetus for oil prices was offset by the U.S. Energy Department's weekly supply report Wednesday. It showed an increase of 10 million barrels, the largest in 13 years, on higher domestic production and imports.

Brent crude was down 27 cents at $109.34 a barrel on the ICE exchange in London.

In other energy futures trading in new York:

— Wholesale gasoline fell 0.7 cent to $3.004 a gallon.

— Natural gas is down 2.7 cents to $4.557 per 1,000 cubic feet.

— Heating oil dropped 0.7 cent to $2.995 a gallon.