At the end of this week, oil prices extended their gains. They increase by about 1% on fears that the Israel-Gaza conflict could spread to the Middle East and disrupt supplies in one of the world's most productive regions

West Texas Intermediate U.S. crude was $90.36 per barrel, up 99 cents, or 1.1%. The more active December WTI contract was $89.13 per barrel, up 76 cents. Brent oil futures rose 77 cents, or 0.8 percent, to $93.15 per barrel at 0042 GMT. And the November contract of the first month expires on Friday. Both contracts are on track for a second weekly gain, with the explosion of a hospital in Gaza this week and the planned ground invasion by Israeli troops raising fears of an extension of the conflict in the Middle East.