By Arathy Somasekhar
HOUSTON, Sept 9 (Reuters) - Brent crude futures breached $100 a barrel on Wednesday for the first time since late July, as Iran and the U.S. hit tankers in the biggest wave of attacks on shipping since the war began, threatening to worsen the ongoing impairment of energy supplies from the Middle East.
Front-month Brent crude futures were up $3.40, or 3.5%, at $101.32 a barrel as of 11:15 a.m. ET (1515 GMT), after touching a high of $101.55. U.S. West Texas Intermediate crude was up $3.45, or 3.7%, at $96.48 a barrel, highest since early June.
Since late May, oil benchmarks have generally traded well below the $100-per-barrel psychological threshold, reflecting expectations that the conflict would remain on a low simmer. Optimism rose in particular after the U.S. and Iran came to a temporary agreement to cease attacks, even though a permanent peace deal had not been reached.
That calculus has been shifting of late with the resumption of strikes. Iran said on Wednesday it had attacked 10 ships near the Strait of Hormuz and the U.S. sank five Iranian oil tankers, in a sharp escalation of the six-month-old war.
