NEW YORK (Bloomberg) - Oil fell for the first time in a week amid renewed signs of swelling crude inventories in the world’s biggest economy.

Futures dropped as much as 1.3% in New York on Monday. Data provider Genscape Inc. said oil stored at a key Oklahoma pipeline hub expanded by 1.5 MMbbl last week, reviving concerns about sluggish demand and ample inventories. Meanwhile, Russia threw cold water on expectations a new round of major supply curbs are imminent.

“Economic uncertainties continue to weigh on prices, as they raise questions around oil demand growth and reduce risk appetite,” said Harry Tchilinguirian, head of commodity and market strategy at BNP Paribas in London.

Oil prices have been under pressure for months as the protracted trade dispute between the U.S. and China erodes demand growth and clouds the worldwide economic outlook. Global markets are “awash” in crude amid booming output from U.S. shale fields, Energy Secretary Rick Perry said in an interview on Sunday.

WTI for December delivery fell $0.61 to $56.05 a barrel at 11:42 a.m. on the New York Mercantile Exchange.

Brent for December settlement fell $0.38 to $61.64 on the London-based ICE Futures Europe Exchange. The global benchmark traded at a $5.59 premium to WTI.

While net-long positions on WTI crude rose in the week ended Oct. 22, those bets are still at half the level they reached last month. That signals there’s still a lot of skepticism, and it will probably take major news to trigger a sustained rally.

“There’s hesitation on heavily long positions to start the week,” said Phil Flynn, senior market analyst at Price Futures Group in Chicago.