By Henning Gloystein

SINGAPORE, May 22 (Reuters) - Oil rose on Monday, pushed by reports that an OPEC-led supply cut may not just be extended into 2018 but might be deepened to tighten the market and prop up prices.

Brent crude futures were up 32 cents, or 0.6 percent, from their last close at $53.93 per barrel at 0643 GMT.

U.S. West Texas Intermediate (WTI) crude futures were back above $50 per barrel, trading up 29 cents, or 0.6 percent, at $50.62.

Both benchmarks have climbed more than 10 percent from their May lows earlier this month.

Prices have risen due to expectations that a pledge by the Organization of the Petroleum Exporting Countries (OPEC) and other producers, including Russia, to cut supplies by 1.8 million barrels per day (bpd) would be extended to March 2018, instead of covering just the first half of this year.

The option of deepening the production cut was also being discussed ahead of a meeting of OPEC and its allies in Vienna on May 25, sources said.

"Oil soared ... as rumours swirled that OPEC... was considering recommending the double whammy of a production cut extension and deeper cuts ahead of this Thursday's meeting," said Jeffrey Halley, analyst at futures brokerage OANDA in Singapore.

James Woods, analyst at Australia's Rivkin Securities, said that a deeper cut may be required to rein in oversupply.

This is because OPEC's oil supplies in 2017 have so far not actually fallen when compared with last year, when oversupply was seen at its worst.

In fact, the U.S. Energy Information Administration (EIA) expects "OPEC net oil export revenues will rise to about $539 billion dollars in 2017, versus 2016".

"The expected increase in OPEC's net export earnings is attributed to slightly higher forecast annual crude oil prices in 2017 as well as slightly higher OPEC output during the year," the EIA said.

Meanwhile, BMI Research said that "despite reducing production in early 2017 in line with the OPEC agreement, Russia will be able to manage its output so that both exports and production will be higher year-on-year in (overall) 2017."

OPEC's and Russia's pledge to tighten the market are also being undermined by oil drillers in the United States.

Goldman Sachs says that the U.S. rig count for new oil production had jumped by 404 since May last year, a rise of 128 percent.

U.S. oil production has already climbed by 10 percent, or almost 900,000 bpd, since mid-2016 to 9.3 million bpd.

(Reporting by Henning Gloystein; Editing by Joseph Radford and Richard Pullin) ((henning.gloystein@thomsonreuters.com; +65 6870 3263; Reuters Messaging: henning.gloystein.thomsonreuters.com@reuters.net))