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From Ahmed Ghaddar

LONDON, March 18 (Reuters) - Brent crude prices jumped more than 4 percent on Wednesday after Iran's Revolutionary Guard threatened to target several energy facilities in Saudi Arabia, the United Arab Emirates and Qatar in retaliation for an attack on Iranian energy facilities, raising the risk of continued supply disruptions from the region.

With no signs of a de-escalation in the conflict with Iran, which has severely disrupted oil exports from the Middle East, Brent crude futures have settled above $100 a barrel in the previous four sessions.

Brent crude futures rose $4.53 , or 4.4 percent, to $ 107.95 a barrel by 1321 GMT on Wednesday, after climbing to $ 108.60 earlier in the session.

U.S. West Texas Intermediate crude rose $ 1.91 , or 2 percent, to $ 98.12 .

“The attacks on Iran’s South Pars field have driven up oil and gas prices, and with any further escalation of attacks on energy infrastructure, prices will continue to rise,” said SEB analyst Ole Hvalby.

Iran’s Fars news agency reported on Wednesday that some tanks and gas facilities at the Asaluyeh refinery in the country were bombed.

Sources at the North Oil Company said that crude oil exports via pipeline have resumed after Baghdad and the Kurdistan Regional Government agreed on Tuesday to restart flows. Two oil officials said last week that Iraq aims to pump at least 100,000 barrels per day of crude oil through the port.

“Despite this development, the easing of pressure on supplies remains limited, as Iraq’s production is only about a third of pre-crisis levels, and oil tanker traffic through the Strait of Hormuz remains largely restricted,” said Soojin Kim, an analyst at MUFG.

Sources reported on March 8 that oil production from the main fields in southern Iraq, where most of Iraq's crude oil is produced and exported, had plummeted 70 percent to just 1.3 million barrels per day as a result of the de facto closure of the Strait of Hormuz due to the war. Approximately 20 percent of the world's oil supply passes through the strait.

The US military said Tuesday it targeted sites on the Iranian coast near the Strait of Hormuz because Iranian anti-ship missiles pose a threat to international shipping there.

Iran confirmed yesterday that the Secretary of the Supreme National Security Council, Ali Larijani, was killed in an Israeli attack.

Oil and gas industry sources quoted the American Petroleum Institute yesterday as saying that U.S. crude oil inventories rose by 6.56 million barrels in the week ending March 13, much more than the roughly 380,000-barrel increase shown in a Reuters poll.