Hedge funds are betting rising tensions around the globe will keep fueling oil’s rebound this year.

Money managers boosted optimistic wagers on West Texas Intermediate crude to the highest since October in the week ended April 16, according to government data released Friday. Total long and short positions swelled to the most in six months, a sign the rally is luring back investors after 2018’s late-year crash. The U.S. benchmark has jumped about 40 percent this year.

Oil surpassed $65 a barrel in New York for the first time since October on Monday as the Trump administration was said to decide it will scrap waivers allowing some allies to import Iranian crude. Conflicts in Libya, Algeria and Venezuela remain wildcards.

“You could see the balance swing a few million barrels in either direction in the next few weeks,' Leo Mariani, an analyst at KeyBanc Capital Markets, said on Friday. “The potential for more supply outages is incredibly high, but the market is also increasingly uncertain.'

The net-long WTI position -- the difference between bets on higher prices and wagers on a decline -- rose 10 percent to 303,366 futures and options contracts, the U.S. Commodity Futures Trading Commission said. Long positions climbed 8.4 percent, while shorts declined 6.5 percent.

Net-length in WTI remains “relatively low' by historical standards, said Daniel Ghali, a TD Securities commodities strategist, signaling more volatility could be ahead.

“Money managers have a lot of room to increase their length,' he said. “The short side might also increase to a lesser extent because prices are now trading above $60 a barrel, which for some people suggests that they might have overshot.’’