Investors cut their bullish bets on the oil price to the lowest level since OPEC reached a deal to cut output last year, amid continued doubts about the effectiveness of that agreement.

Saudi Arabia’s conventional approach to market management is no longer working: crude has fallen back below $50 a barrel, US shale oil output is again on the rise and Saudi-led Opec, if anything, is worse off than when it agreed the supply deal back in November, having cut volumes for little upside on price.

The resurgence of the US shale industry after the oil slump of 2014 was a key factor in how crude prices fell sharply last week, to back below $50 per barrel. The market is concerned about whether efforts by Opec, the producers’ cartel, to tackle a supply glut by curbing output will be undermined by reinvigorated US shale companies.

U.S. crude CLcv1 rose 2.09 percent to $46.47 per barrel and Brent LCOcv1 was last at $49.45, up 2.21 percent on the day.

"The good news is that the market is moving towards rebalancing," Saudi Aramco CEO Amin Nasser said at the International Oil Summit in Paris last week. "There has also been a rapid drawdown of floating storage in the first quarter of this year. This is being driven by improving fundamentals and the OPEC deal."

Baker Hughes Incorporated (NYSE:BHI) announced today that the international rig count for April 2017 was 956, up 13 from the 943 counted in March 2017, and up 10 from the 946 counted in April 2016. The international offshore rig count for April 2017 was 201, up 4 from the 197 counted in March 2017, and down 19 from the 220 counted in April 2016.

U.S. crude CLc1 fell $2.05 or 4.3 percent to $45.77, by 12:08 p.m. Brent was down $2.07, or 4.1 percent to $48.71.

OPEC and non-OPEC oil producers look likely to extend their agreement to limit supplies beyond its June expiry to help clear a glut, three OPEC delegates said on Thursday, downplaying the chance of additional steps such as a bigger cut.

Saudi Arabia, the world’s largest crude exporter, cut pricing for June oil exports to Asia as it fights to defend sales in its biggest regional market. The kingdom raised pricing to all other regions.

NYMEX crude for June delivery CLc1 was down 12 cents at $49.21 a barrel by 0619 GMT. London Brent crude for new front-month delivery in July LCOc1 was down 15 cents at $51.90.

U.S. West Texas Intermediate (WTI) crude oil futures were trading at $49.37 per barrel at 0644 GMT, down 25 cents, or 0.5 percent from their last close. WTI has lost around 8.5 percent in value from its April peak. Brent crude futures, the international benchmark for oil prices, were at $51.63 per barrel, down 19 cents, or 0.37 percent. Brent is almost 9 percent below its April peak.

The World Bank is holding steady its crude oil price forecast for this year at $55 per barrel, increasing to an average of $60 per barrel in 2018. Rising oil prices, supported by production cutbacks by Organization of the Petroleum Exporting Countries (OPEC) and non-OPEC states, will allow markets to gradually rebalance. These oil price forecasts are subject to downside risks should the rebound in the U.S. shale oil industry be greater than expected.

Brent crude futures were at $53.34 per barrel at 0715 GMT (3:15 a.m. ET), up 41 cents, or 0.77 percent, from their last close. U.S. West Texas Intermediate (WTI) crude futures were up 32 cents, or 0.63 percent, to $50.76 a barrel.

"There is consensus building but it's not done yet," he told reporters on the sidelines of a conference in the United Arab Emirates. Asked about non-OPEC producer Russia, Falih replied: "We are talking to all countries. We have not reached an agreement for sure, but the consensus is building."

The crude oil contract for May delivery on the New York Mercantile Exchange fell 53¢ on Apr. 17 to close at $52.65/bbl. The June contract lost 49¢ to $53.11/bbl. The natural gas price for May declined 6.4¢ to a rounded $3.16/MMbtu. The Henry Hub cash gas price closed Apr. 17 at $3.06/MMbtu, up 8¢. The Brent crude contract for June on London’s ICE also declined 53¢, settling at $55.36/bbl. The July contract was down 49¢ to $55.88/bbl. The gas oil contract for May lost 25¢ at $497.75/tonne. The average price for OPEC’s basket of benchmark crudes on Apr. 17 was $52.94/bbl, down 43¢.