Oil retreated from a six-week high as ambiguous progress in U.S.-China trade talks and worsening violence in Hong Kong damped sentiment across financial markets.

Futures fell as much as 1.7% in New York after President Donald Trump said over the weekend that, while discussions with Beijing are moving along “very nicely,” an agreement hasn’t been reached and that he wouldn’t eliminate all tariffs. Oman’s Oil Minister Mohammed Al Rumhy said OPEC and its partners are unlikely to announce deeper production cuts when they meet next month, adding to concerns of a surplus in early 2020.

“These days it’s largely the trade war” that’s moving prices, Bob McNally, president of Rapidan Energy Group and a former oil official at the White House under President George W. Bush, said in a Bloomberg TV interview on Monday. “Folks are also looking into early next year and seeing an oversupplied market, and there’s questions whether OPEC+ will rise to the challenge.”

Oil has rallied around 11% since early October as the world’s two largest economies moved closer toward a limited trade agreement, prompting hedge funds to cautiously revive bets on rising prices. Yet the gaps have been capped as the world’s two biggest oil consumers struggle to clinch a final deal.

WTI for December delivery fell 92 cents, or 1.6%, to $56.32 a barrel on the New York Mercantile Exchange as of 10:49 a.m. in London. It settled 0.2% higher on Friday at $57.24, the highest close since Sept. 24.

Brent for January dropped 1.5% to $61.60 a barrel on the London-based ICE Futures Europe Exchange after climbing 1.3% last week. The global crude benchmark traded at a $5.29 premium to WTI for the same month.