NEW YORK, March 19 (Reuters) - U.S. gasoline pump prices have jumped more than 30% this month, moving toward $4 a gallon despite efforts by President Donald Trump to curb price increases and contain supply disruptions stemming from the Middle East war.

U.S. national average retail gasoline prices have climbed about 90 cents a gallon, or more than 30%, since the U.S. and Israel attacked Iran at the end of February. The average pump price on Thursday was $3.88 a gallon, according to data from the American Automobile Association or AAA.

Analysts said they expect pump prices to go higher, as crude prices continue to surge. U.S. West Texas Intermediate crude futures have jumped nearly $30, or 43%, from $67.02 a barrel to $96.14 over the same period.

"It now looks like gasoline will hit $4/gal next week and could head toward $4.10/gal and beyond," wrote GasBuddy analyst Patrick De Haan on X. 

The $4 per gallon milestone, last reached in August 2022, will further pressure consumers already strained by inflation. Surging pump prices have become a political headache for Trump and his Republican Party, which will soon be campaigning to hold onto thin majorities in the U.S. Congress in November midterm elections.

Trump had vowed to lower energy prices and ramp up U.S. oil and gas production. But so far, much of his second term has been marked by volatile markets, shifting policies like tariffs and geopolitical turmoil.

The U.S.-Israeli war on Iran has choked supplies from one of the world's top oil-producing regions, as Iran's attacks on shipping in the Strait of Hormuz have disrupted exports from producers in the Middle East.

Retail fuel prices have surged in tandem with oil prices, driven by increasing feedstock costs.

TOO LITTLE, TOO LATE?

This week, the Trump administration announced a 60-day waiver of the Jones Act shipping law. The step will temporarily allow foreign-flagged vessels to move fuel, fertilizer and other goods between U.S. ports. Industry insiders expect it to have only a marginal impact on price increases.

"Oil prices are set independently of transportation costs. The waiver will only allow additional ships to carry supplies," said a fuel trading source who was not authorized to speak on the record.

"I don't think it will dramatically lower prices," the source added. 

"Motorists hoping for a plummet at the pump from the Jones Act waiver are probably going to be disappointed," GasBuddy's De Haan said.

The Trump administration is also expected to announce a decision to waive summer gasoline regulations which would temporarily lift federal smog-cutting restrictions on summer-blend gasoline.

Such a waiver could shave 10 to 20 cents a gallon off retail gasoline prices, De Haan said, adding that consumers in cities including Chicago, New York and Washington, D.C., where reformulated gasoline is used, may save the most at the pump.