* Greece PM's call for bailout referendum weighs on oil
* Weak China, UK PMI data adds pressure on oil, equities
* Euro weakness, dollar strength, weighs on oil
* Coming up: API stocks data, 4:30 p.m. EDT Tuesday (Recasts, updates prices, market activity)
By Robert Gibbons
NEW YORK, Nov 1 Brent crude prices edged lower on Tuesday in volatile trade as a possible referendum in Greece on its debt bailout revived concerns about the euro zone and weak global economic data pointed to further slowing.
Brent and U.S. crude fell a third straight session, but both pared losses after a media report said there was growing opposition from Greek lawmakers to Prime Minister George Papandreou's call for a referendum.
Papandreou's unexpected move had sent the euro, equities and oil prices sharply lower along with economic data from China, Britain and the United States that reinforced concerns about slowing economies curbing oil demand. [ID:nL5E7M1087]
The Greek government faced possible collapse as ruling party lawmakers demanded that Papandreou resign for throwing the nation's euro membership into jeopardy with his call for a referendum.
Investors also monitored reverberations from Monday's bankruptcy filing by brokerage MF Global Holdings Ltd MF.N.
"A big part of the day's downdraft came from the surprise referendum announcement from Greece and the turmoil at MF Global is adding to the general bearish mood of the market," said Mark Anderle, a broker at TAC Energy in Dallas.
ICE Brent December crude LCOc1 fell only 2 cents to settle at $109.54 a barrel, having slumped as low as $106.10.
U.S. December crude CLc1 fell $1 to settle at $92.19 a barrel, ending back above its 100-day moving average of $89.53 after tumbling to $89.17.
Brent's premium to its U.S. counterpart CL-LCO1=R increased, moving back above $17 a barrel.
Crude trading volume improved from Monday's anemic totals, with U.S. volume only 14 percent below its 30-day average and Brent 3 percent below its 30-day average. Both surpassed half a million lots traded and topped the previous session's totals.
Euro zone debt crisis in graphics:
Singapore International Energy Week: [ID:nL3E7LR0VG]
TABLE-OPEC oil output in October: [ID:nL5E7LV2IX]
U.S. stocks also cut losses after tumbling 3 percent after the report of growing opposition in Greece to a referendum. European shares gave a large slice of October gains and posted the biggest one-day loss in over a month on the intensified anxiety over the euro zone debt crisis. [.N] [.EU]
"Risk aversion is back," said Eugen Weinberg, head of commodities research at Commerzbank. "The solution to the euro zone debt crisis that we thought we were celebrating last week no longer seems certain."
Copper fell more than 3 percent on the Greece referendum fallout and on an unexpected slowdown in factory activity in top metals consumer China. [MET/L]
Global growth expectations weakened on reports from several key economies showing manufacturing slowing.
China's official purchasing managers' index (PMI) fell in October to its lowest level since February 2009.[ID:nL5E7M100M]
The pace of growth in the U.S. manufacturing sector slowed in October, according to the Institute for Supply Management, against expectations, though improvement in new orders sounded a supportive note in a chorus of gloom. [ID:nN1E7A00N9]
The UK PMI survey showed the manufacturing sector fell in October at its sharpest rate since June 2009. [ID:nL5E7M119D]
U.S. OIL INVENTORIES
Ahead of weekly reports on U.S. oil inventories, MasterCard said U.S. retail gasoline demand fell last week even as average retail pump prices dipped slightly. [ID:nN9E7G300B]
U.S. crude inventories were expected to have risen last week, by 1.1 million barrels, while distillate and gasoline stockpiles fell, a Reuters survey of analysts showed. [EIA/S]
The industry group American Petroleum Institute's data is due at 4:30 p.m. EDT (2030 GMT) on Tuesday. The U.S. Energy Information Administration's report follows on Wednesday morning. (Additional reporting by Gene Ramos in New York, Christopher Johnson and Zaida Espana in London and Rebekah Kebede in Singapore; Editing by David Gregorio and Andrea Evans)