Oil surged almost $3 a barrel after Reuters reported Iranian oil exports will drop by 300,000 barrels a day this month because of tighter sanctions.

Futures jumped more than 2 percent in three minutes on the New York Mercantile Exchange, topping $108 a barrel for the first time in four days.

Oil has risen this year as Western countries imposed sanctions on Iran’s petroleum exports aimed at halting its nuclear program. Iran threatened to shut the Strait of Hormuz, a transit route for a fifth of the world’s oil, in retaliation.

Futures fell earlier this week as Saudi Arabia said it could boost output immediately to make up for any supply shortfall.

Crude oil for May delivery rose to $108.25 a barrel. Prices have risen 3 cents this week and are up 8.4 percent this year.

Brent oil for May settlement gained $2.19, or 1.8 percent, to $125.33 a barrel on the London-based ICE Futures Europe exchange.