July 23 (Reuters) - U.S. energy shares rose in premarket trading on Thursday as Brent crude briefly touched $100 a barrel, extending a five-day rally after attacks on two Saudi oil tankers intensified Middle East tensions and heightened concerns over global oil supply disruptions.

Houthi forces in Yemen have widened the conflict by targeting vessels carrying Saudi oil in the Bab el-Mandeb strait, after declaring a naval blockade on Saudi shipments.

The attacks have heightened fears that disruptions to Middle East oil exports could spread beyond the Strait of Hormuz, tightening global crude supplies and supporting higher energy prices.

Here are more details:

-- Brent crude futures rose as much as 6.3% to $100 per barrel by 1302 GMT for the first time since May 26. U.S. West Texas Intermediate crude was up 5.2% at $91.30 per barrel.

-- "We continue to expect the production recovery process in the Middle East to be slower than the market anticipates, as it requires an increase in inbound vessels," said UBS analyst Giovanni Staunovo.

-- "With the conflict resuming, those flows remain depressed. This should keep the oil market tight and prices supported."

-- Shares of Exxon Mobil and Chevron ( CVX ) rose 1.6% and 1.7%, respectively. Diamondback Energy ( FANG ) , Devon Energy ( DVN ), ConocoPhillips ( COP ) and Occidental Petroleum ( OXY ) were up between 2% and 2.5%.

-- Refiners Valero Energy ( VLO ) , Marathon Petroleum ( MPC ) and Phillips 66 also gained between 2.1% and 2.6%.

-- Before tensions flared again after July 8, analysts had cut their 2026 oil price forecasts for the first time since the Iran war began, a Reuters poll showed in June.

-- Energy stocks have swung with developments in the conflict, surging on supply disruption fears before pulling back after the United States and Iran reached a temporary peace agreement.