By Sarah McFarlane and Jenny W. Hsu

Crude futures surged Wednesday on growing optimism that OPEC would be able to deliver a production-cut deal later in the day.

Prices jumped after Iran's oil minister, Bijan Zanganeh, said in Vienna that he believed Organization of the Petroleum Exporting Countries would reach a deal, though he said an immediate freeze of his country's output wasn't on the agenda.

An OPEC deal would be aimed at cutting into a global oversupply of oil that has severely depressed prices since 2014. A proposal would likely have the group cut production by more than a million barrels a day, which represents about 1% of the global oil supply.

The February contract in Brent crude, the global oil benchmark, was up 5.7% to $50.02 a barrel on London's ICE Futures exchange, according to Factset. On the New York Mercantile Exchange, West Texas Intermediate futures were trading up 5.3% at $47.61 a barrel, Factset said.

"The communication this morning is extremely positive from Iran," said Bjarne Schieldrop, a commodities analyst from Sweden's SEB bank, adding that the market was volatile ahead of the meeting's outcome.

Iran's willingness to participate in some way--a long-held Saudi demand--signals a greater likelihood that all OPEC members will agree to a deal.

A successful OPEC accord is also crucial in getting non-OPEC producers--like Russia--to slash production in a collective effort to lift global oil prices. Russia has said it wouldn't make any commitment until an agreement was forged by OPEC members.

In the past year, OPEC leaders have tried several times to agree on production curbs, but these attempts have failed.

Tension between Iran and Saudi Arabia has also been a sticking point. Even though Iran has relaxed its position by agreeing to hold production levels steady--a step back from a previous demand to keep pumping--it remains to be seen whether Saudi Arabia will be satisfied.

"The fact that geopolitical rivals, Saudi Arabia and Iran, appear to have problems resolving their differences on the allocation of any cartel-wide production cuts seems to be the major stumbling block to any agreement," said Barnabas Gan, an economist at OCBC bank in Singapore.

Iraq, OPEC's second-largest producer after Saudi Arabia, also wants to be excluded from a deal, saying it would only go as far as capping production at present levels. Iraq says it needs the oil revenue to fund its war against Islamic State.

If OPEC fails to reach an agreement, a "blame game" could ensue, with Saudi Arabia pointing fingers at Iran and Iraq for being unwilling to compromise, said Tim Evans, a Citi Futures analyst.

"This apparent stalemate has seen investors take an increasingly bearish view on oil prices," said ANZ Research. ANZ added that despite the squabbling, OPEC is under growing pressure to deliver a deal to protect its relevance.

Nymex reformulated gasoline blendstock--the benchmark gasoline contract--rose 3.6% to $1.43 a gallon. ICE gasoil changed hands at $445.75 a metric ton, up $20.25 from the previous settlement.

Write to Sarah McFarlane at sarah.mcfarlane@wsj.com and Jenny W. Hsu at jenny.hsu@wsj.com

(END) Dow Jones Newswires

November 30, 2016 05:29 ET (10:29 GMT)

Copyright (c) 2016 Dow Jones & Company, Inc.