SANTA CRUZ, Bolivia  - OPEC will need to extend supply cuts when it meets next week to end years of global oil oversupply, oil ministers from two OPEC members said on Wednesday, just over a week before the group meets to discuss supply policy.

The Organization of the Petroleum Exporting Countries, non-member Russia and nine other producers agreed to curb oil output by about 1.8 million barrels per day until March 2018. They are expected to extend the deal at a Nov. 30 meeting in Vienna.

Top crude exporter Saudi Arabia is lobbying oil ministers to extend output cuts by nine months, sources familiar with the matter said.  

"In my view, an extension of the agreement will help us in stabilizing the market," Qatar Oil Minister Mohammed al-Sada said on the sidelines of a gas exporter meeting in Santa Cruz, Bolivia, on Wednesday.

OPEC has been successful in bringing global oil inventories closer to their five-year average, but the group needs more time to tighten supply further, he said.

The oil market has found some balance as inventories decline, Venezuela's Oil Minister Eulogio Del Pino said at the same event. He put the optimal price for crude at between $60 and $70 dollars a barrel to encourage investment.

U.S. crude CLc1 hit a two-year high of $58.05 a barrel on Wednesday, while Brent crude LCOc1 rose 55 cents, or 0.9 percent, to $63.12 a barrel.

Rising U.S. shale oil production has made it harder for OPEC to reduce the global glut. U.S. output hit a weekly record this week at more than 9.6 million bpd, approaching the 10 million bpd monthly record output levels reached in the 1970s.



ANOTHER EXCESS

The gas market, which also facing oversupply due to growing output of shale gas and rising production of liquefied natural gas (LNG), could find a balance around 2025 after the excess of supply peaks in 2020, al-Sada said.

In anticipation of that balance, Qatar this year lifted a self-imposed ban on the development of the world's biggest natural gas field, which will allow it to boost production in coming years.

The vast offshore gas field shared with Iran accounts for nearly all Qatar's gas output and around 60 percent of its export revenue.

The chairman of Spain's Repsol REP.MC , Antonio Brufau, said the global gas market is undergoing a deep transformation with rising LNG supply, lower production costs and traditional suppliers considering non-conventional projects such as shale.

"LNG is shaking up the market," he said.

(Editing by Simon Webb, Cynthia Osterman and David Gregorio) ((david.gaffen@thomsonreuters.com; +1-646-223-6064; Reuters Messaging: david.gaffen.reuters.com@reuters.net))