By Alison Sider, Sarah McFarlane and Jenny W. Hsu

Oil prices continued their downward slide Tuesday amid continued doubts that the global crude glut is being drained.

Oil is on track for its seventh consecutive day of declines, which would be its longest losing streak since March. That reflects recent investor concern about the strength of rebounding U.S. oil production and ebbing faith that the Organization of the Petroleum Exporting Countries can effectively lead the market back into balance after several years of oversupply.

"Without signs that the overhang in the market is being eliminated, the market is showing real trouble justifying plus-$50 oil," said Gene McGillian, research manager for Tradition Energy.

U.S. crude futures were recently down 16 cents, or 0.33%, to $49.07 a barrel on the New York Mercantile Exchange. Brent, the global benchmark, was down 10 cents, or 0.19%, at $51.50 a barrel on ICE Futures Europe.

OPEC and other major producers have agreed to cut production by 1.8 million barrels a day in the first half of 2017. But because stocks have remained high, traders and investors are now watching to see whether the cartel will extend the deal when it meets in May.

"Until OPEC announces an official decision on whether to extend the production cuts, the main focus of the market will be on that," said Nelson Wang, an energy analyst at CLSA.

And with uncertainty about whether the cuts will continue, market participants have turned their focus to signs that U.S. production will come on strong. Analysts say the recent downtrend may persist as U.S. oilfield-service companies, namely drillers, still have plenty of spare capacity.

Mr. Wang estimates only around 70% of available oil rigs in the U.S. are currently in operation despite persistent growth this year in drilling activity there. Baker Hughes's closely watched rig count is at its highest level in nearly two years.

"This means there is a lot of upside risk to U.S. supplies," he said.

Gasoline futures fell 1.46 cents, or 0.9%, to $1.6068 a gallon. Diesel futures fell 0.88 cent, or 0.59%, to $1.5339 a gallon.

Write to Alison Sider at alison.sider@wsj.com, Sarah McFarlane at sarah.mcfarlane@wsj.com and Jenny W. Hsu at jenny.hsu@wsj.com

(END) Dow Jones Newswires

April 25, 2017 11:41 ET (15:41 GMT)

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