Brent crude oil soared more than 4 percent towards $59 a barrel on Thursday after Saudi Arabia and its Gulf Arab allies began a military operation in Yemen, which sits on a key shipping passage between Europe and the Arab Gulf.
The air strikes against Houthi rebels, who have driven the president from Yemen's capital Sanaa, could stoke concerns about the security of Middle East oil shipments if the conflict widens.
Brent futures were up $2.47 at $58.93 by 1158 GMT. U.S. crude was up $2.16 at $51.37 a barrel.
Brent and U.S. crude prices spiked around 6 percent earlier in the session but pared gains in European trading.
The air strikes against Houthi rebels, who have driven the president from Yemen's capital Sanaa, could stoke concerns about the security of Middle East oil shipments if the conflict widens.
Brent futures were up $2.47 at $58.93 by 1158 GMT. U.S. crude was up $2.16 at $51.37 a barrel.
Brent and U.S. crude prices spiked around 6 percent earlier in the session but pared gains in European trading.