Brent fell to $106.04 a barrel as traders weighed possible Russian fuel supplies against threats to Gulf shipping and energy infrastructure.
Oil rises as Saudi supply concerns outweigh Russian diesel prospects
Brent gained 0.8% to $106.58 a barrel as traders assessed fighting involving Saudi Arabia and the potential for more Russian diesel exports.

Crude futures advanced on October 14 as concerns about Saudi supply competed with expectations of additional diesel exports from Russia. At 12:30 a.m. GMT, Brent was up 89 cents, or 0.8%, at $106.58 a barrel. U.S. West Texas Intermediate gained 80 cents, or 0.9%, to $94.94 a barrel.
Hiroyuki Kikukawa, chief strategist at Nissan Securities Investment, attributed the gains to supply worries arising from fighting between Saudi Arabia and Yemen's Iran-allied Houthis. He said expectations of higher Russian diesel exports could ease tightness in the market.
Saudi Arabia's energy ministry said a Houthi attack on a Saudi Aramco administrative building in Dhahran caused a limited fire. The group has launched missiles and drones at Saudi Arabia in retaliation for the kingdom's backing of Yemeni government forces.
Russia's government said it saw no direct connection between negotiations with Ukraine and an agreement to supply diesel to the United States. Its comments followed a media report that U.S. envoys had described the agreement to Ukrainian officials as part of an effort to bring Russia back into peace negotiations.
