Oil prices rose about 4% on May 13 as U.S. gasoline prices jumped to an all-time high, stock markets soared and on fears supplies would tighten if the EU bans Russian oil after Moscow sanctioned European units of state-owned Gazprom.

Brent futures rose $3.97, or 3.7%, to $111.42/bbl by 12:32 p.m. EDT (1632 GMT), while WTI crude in the U.S. rose $4.38, or 4.1%, to $110.51.

U.S. gasoline futures soared to an all-time high, boosting the gasoline crack spread—a measure of refining profit margins—to its highest since it hit a record in April 2020 when WTI settled in negative territory.

The U.S. 3:2:1-crack spread, another measure of refining margins that includes both gasoline and diesel, rose to a record, according to Refinitiv data going back to May 2021.

Automobile club AAA said U.S. pump prices have risen to record highs of $4.43 per gallon for gasoline and $5.56 for diesel.

WTI was on track for its highest close since March 25 and its third weekly rise. Brent, however, remained set for its first weekly decline in three weeks.

Oil prices have been volatile, supported by worries an EU ban on Russian oil could tighten supplies but pressured by fears that a resurgent COVID-19 pandemic or other factors could cut global demand.

“An EU embargo, if fully enacted, could take about 3 million bbl/d of Russian oil offline, which will completely disrupt, and ultimately shift global trade flows, triggering market panic and extreme price volatility,” said Rystad Energy analyst Louise Dickson.

This week, Moscow slapped sanctions on the owner of the Polish part of the Yamal natural gas pipeline that carries Russian gas to Europe, as well as the former German unit of the Russian gas producer Gazprom, whose subsidiaries service Europe’s gas consumption.

In China, stocks rose as authorities pledged to support the economy and city officials said Shanghai would start to steadily ease coronavirus traffic restrictions and open shops this month.

SPI Asset Management managing partner Stephen Innes said in a note that oil traders were looking “for a glimmer of light at the end of China's gloomy lockdown tunnel.”

“Still, we continuously end up at square one with lower case counts weighted against the authorities doubling down on their zero COVID policy,” Innes added.

Global shares rose on Friday and investor sentiment stabilized after a volatile week of trading, helping to push up stock indexes in the U.S. and Europe.

Pressuring oil prices during the week, inflation and rate rises drove the U.S. dollar to a near 20-year high against a basket of other currencies, making oil more expensive when purchased in other currencies.

The EU said there was enough progress to relaunch nuclear negotiations with Iran. Analysts said an agreement with Iran could add another 1 million bbl/d of oil supply to the market.