WTI crude rose more than 3 percent on Tuesday as a weaker dollar propped up commodities priced in the currency, prompting short-covering in a market that has sold off with little pause over the past seven months.
Even so, gains in oil were capped by fears of another large build in U.S. crude stocks, traders said.
U.S. crude stocks are seen rising 3.8 million barrels, on average, in the week to Jan. 23, according to a Reuters poll, adding to the previous week's build of over 10 million barrels, which was the biggest in 14 years to the highest level for this time of year on record.
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The American Petroleum Institute, an industry group, will release its weekly inventory report at 2130 GMT. Government data will be issued on Wednesday morning.
Genscape, which tracks oil inventories, reported a near 2.4 million-barrel build last week in Cushing, the Oklahoma delivery point for U.S. crude futures, a market source said.