(Bloomberg) -- Oil plummeted and gasoline futures tumbled after a U.S. government report showed swelling fuel stockpiles and slowing demand as the coronavirus pandemic rages.Crude futures in New York declined as much as 3.9% on Wednesday, while gasoline futures dropped over 4%. Domestic gasoline inventories rose 1.9 million barrels last week, the biggest increase since May, while a measure of gasoline consumption slid to the lowest since late September, according to an Energy Information Administration report. The mounting fuel supplies and lackluster demand may worsen during the normally sluggish winter driving months.“The resurgence in Covid-19 has put a pause in the expectation that we’d see increased demand,” said Brian Kessens, a portfolio manager at Tortoise, a firm that manages roughly $8 billion in energy-related assets. “The build in gasoline is an indicator that we are seeing that truly play out.”Rising coronavirus infections worldwide are putting a damper on an already murky demand outlook, with governments imposing or considering tighter restrictions. Milan, Italy’s financial capital, will be under night-time curfew beginning this week, while Germany’s new infections reached a record. In the U.S., New York posted more than 2,000 new Covid-19 cases for the first time since May.JBC Energy cut its outlook for oil-products demand this year and early 2021, saying that “the persistent lack of recovery in U.S. gasoline demand remains particularly worrisome.”Flagging fuel demand highlights the importance of ongoing discussions over the next round of U.S. virus aid to reviving energy consumption. White House Chief of Staff Mark Meadows said the goal in talks with House Speaker Nancy Pelosi is a deal on a coronavirus relief package within the next 48 hours, though any agreement likely faces a roadblock in the Republican-controlled Senate.“There’s concern about the growing virus caseload in a lot of places hitting demand, especially if there’s not some fiscal stimulus,” said Michael Lynch, president of Strategic Energy & Economic Research. “Global inventories are still quite high and they’re not going to come down until we get a stronger demand recovery. Now, it looks like that will be pushed further out into the future.”The surprise gasoline build led to another leg lower for refining margins. The so-called crack spread for combined gasoline and diesel against WTI futures slumped to the lowest since early April, providing little incentive for refiners to churn out more product in the midst of depressed demand.“There’s no reason for these guys to run the refinery. It’s a losing proposition,” said Bob Yawger, head of the futures division at Mizuho Securities. “There’s nobody that’s in a hurry to bring refinery utilization rates back up.”In another sign of weakness, the EIA report showed a fifth straight weekly build at the nation’s biggest storage hub in Cushing, Oklahoma. Crude inventories there are now over 60 million barrels for the first time since May. The spread between WTI’s nearest contracts weakened to its widest contango structure in about a week, signaling concerns of oversupply.Still, distillate stockpiles decreased 3.83 million barrels last week and crude stockpiles dropped just over 1 million barrels, the government data showed.For more articles like this, please visit us at bloomberg.comSubscribe now to stay ahead with the most trusted business news source.©2020 Bloomberg L.P.