* Libya leads increase in OPEC oil supply
* Saudi Arabia trims output after big November increase
* Output falls in Angola, Nigeria (Adds quotes from paragraph 5)
By Alex Lawler
LONDON, Jan 4 (Reuters) - OPEC oil output rose in December to the highest since October 2008, a Reuters survey found on Wednesday, as members showed little sign yet of lowering output to make room for recovering Libyan supplies.
Supply from all 12 members of the Organization of the Petroleum Exporting Countries averaged 30.74 million barrels per day (bpd) last month, up from a revised 30.62 million bpd in November, the survey of sources at oil companies, OPEC officials and analysts found.
The survey indicates OPEC, source of more than a third of the world's oil, is producing more than the target of 30 million barrels daily it adopted at a Dec. 14 meeting, as oil prices well above $100 a barrel provide little incentive for supply cuts.
In December, the biggest increase in OPEC supply came from Libya, where production continues to recover after being virtually shut down during the uprising which toppled Muammar Gaddafi.
"It's quite surprising how successful the Libyans have been so far," said Samuel Ciszuk, consultant at KBC Energy Economics.
December's total is OPEC's highest since October 2008, shortly before the group agreed to a series of supply curbs to combat recession, based on Reuters surveys.
Libyan oil exports and refinery demand have climbed to 750,000 bpd in December, according to the survey, up 250,000 bpd from November but some way short of the production figures given by Libyan officials.
Oil prices traded lower on Wednesday, before rallying after diplomats said the European Union had reached a deal in principle to ban imports of Iranian oil. Brent crude was up $1.23 to $113.36 a barrel as of 1447 GMT.
The survey also provides little evidence Gulf Arab OPEC producers are curbing output drastically, so far, to make way for increased Libyan output.
Saudi Arabia and its Gulf OPEC allies raised production unilaterally in the second half of 2011 after failing to convince Iran and other members to agree to a coordinated increase to meet the shortfall in supplies from Libya.
OPEC settled the six-month-old argument at its December meeting in Vienna meeting by adopting the 30 million bpd target. However, analysts have said that without defined individual national quotas, leakage above the new limit remains very possible.
In November, supply from Saudi Arabia was revised 350,000 bpd higher to 9.8 million bpd as it shipped more crude to customers in Asia. In December, output dipped only slightly, according to sources in the survey.
"In November, there was a very sharp uptick and what I'm seeing in December is practically no change - a small reduction maybe, but not a significant one," a shipping industry source said.
Kuwait increased production in December and supply nudged higher in the United Arab Emirates. Sources in the survey have lower estimates of Kuwaiti supply than Kuwaiti industry officials, who say the country is pumping 3 million bpd or more.
Venezuelan output also was pegged slightly higher. Major maintenance was completed at the Petroanzoategui heavy crude upgrader in December.
Among the countries with reduced output, Angolan shipments declined due to lower exports of crude grades including Girassol and Plutonio. Loading schedules point to steady to lower shipments in January.
Nigerian output was trimmed as Royal Dutch Shell shut down output at its offshore Bonga site because of an oil spill. (Additional reporting by Amena Bakr; Editing by Anthony Barker)