Gas prices across the U.S. are expected to continue rising following Russia's invasion of Ukraine, but how much remains in question.

Patrick De Haan, head of petroleum analysis at GasBuddy, predicted in a post-invasion news conference Thursday that there would be incremental increases over the next few weeks with the potential for larger ones down the road.

"This was not necessarily a shock, with the headlines coming out of the White House, but now that Russia has attacked Ukraine, the situation escalates," De Haan said.

The invasion could escalate a potential disruption in the flow of oil out of Ukraine, the source of about 60,000 barrels a day.

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De Haan also pointed to the possibility that Russia could use oil as a weapon, hitting back at Western sanctions by limiting supply. The nation is the world's third-largest oil producer after the U.S. and Saudi Arabia, producing about 10.5 million barrels a day, according to the U.S. Energy Information Administration.

Pump prices had already risen in recent weeks as markets anticipated Russia's invasion of Ukraine. Here's a look at Sunday's prices, according to GasBuddy:

• The national average was $3.60 a gallon. It was up a 8 cents for the week, 24 cents for the month and 87 cents compared to a year ago.

• Gas cost an average $3.27 a gallon in the Houma-Thibodaux area. That was up 7 cents for the week, 30 cents for the month and 98 cents compared to a year ago.

• Louisiana’s average, $3.34 a gallon, was up cents for the week, 31 cents for the month and 96 cents for the year.

Louisiana's average price for this time of year is its highest since 2014, according to GasBuddy.

The American Automobile Association reported a national average of $3.60 Sunday. The highest U.S. average price on record is $4.11 in July 2008.

Motorists will face higher costs immediately, but it may take weeks before customers see significant increases, De Haan said. If the war and its fallout continue, the U.S. is on track to hit a $4-per-gallon national average by April or May.

"For gas prices to drop, it would take either a drop in global demand or an increase in global supply, both of which seem unlikely," DeHaan said.

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Oil prices have risen as Russia built up its military forces near the Ukraine border in recent weeks. After the invasion Thursday, Brent crude, the world benchmark, jumped briefly above $105 a barrel for the first time in nearly eight years. It closed trading Friday at just under $98 a barrel.

"Crude prices surged after Russia launched its military invasion of Ukraine this morning," the AAA said Thursday. "As the conflict escalates with more sanctions and retaliatory actions, the oil markets will likely respond by continuing to increase the price of crude oil to reflect more risk of disruption to tight global oil supplies."

Total U.S. crude stocks increased by 4.5 million barrels last week to total 416 million barrels, the AAA noted.

"The current stock level is approximately 10% lower than mid-February 2021, contributing to pressure on domestic crude prices," the group said.

Grace Altenhofen is a news reporting intern for the Des Moines Register. Keith Magill is executive editor at The Courier and Daily Comet. Both newspapers are part of the USA Today Network.

This article originally appeared on The Courier: How high might gas prices rise in wake of Russia invading Ukraine?