UPDATE 4-Oil drops on U.S. inventory rise

* U.S. crude stocks rise, gasoline stocks decline - EIA weekly report

* Bearish monthly reports from OPEC, EIA and IEA

* U.S. crude oil inventories fall 1.4 mln barrels

(Recasts with changing prices, adds quote, weekly EIA report)

LONDON, March 13 (Reuters) - Oil prices fell on Wednesday on a rise in U.S. stockpiles and a mildly bearish weekly report from the West's energy agency, with benchmark Brent crude dropping below a key $109 a barrel level.

U.S. crude inventories rose last week as imports increased, and gasoline fell as refineries processed less oil, government data from the Energy Information Administration (EIA) said.

Monthly reports from the world's three main energy agencies also put pressure on prices.

A report by the West energy watchdog, the International Energy Agency that output in the United States would be enough to protect against most potential supply shocks put pressure on prices.

Analysts did not rule out further falls. "Watching the 200-day moving average (currently at $109.38 a barrel) is going to be key - if Brent breaks this barrier, you could see pressure again," said oil analyst Olivier Jakob at Petromatrix in Zurich.

Brent crude fell 88 cents to $108.79 a barrel by 1550 GMT, after swinging between a high of $109.89 and a low of $109.06 earlier in the session.

U.S. oil rose 18 cents to $92.72, gaining for a fifth day in the longest daily winning streak since mid-December.

The Organization of the Petroleum Exporting Countries (OPEC) on its part warned in its monthly report that demand growth could miss forecasts due to economic weakness and that growing U.S. supply would hit its highest in three decades.

But it left its forecast for growth in global oil consumption unchanged for now, still expecting an expansion of 840,000 barrels per day (bpd) this year.

OPEC, the source of more than a third of the world's oil, expects the U.S. economy to expand by 1.7 percent in 2013, down from the 1.8 percent previously thought. Growth in the euro zone is now seen contracting by 0.2 percent, having earlier been expected to expand slightly.

DEMAND OUTLOOK

A similar monthly report by the EIA cut its 2013 world oil demand forecast slightly, but also cut the forecast for non-OPEC output.

Uncertainty over Europe's economic outlook, worries about central banks pulling the plug on easy monetary policy and concerns of an uneven recovery in China have shaved around $10 a barrel off Brent since its high of more than $119 in February.

"For developing Asia, the outlook is less positive, where leading indicators point towards a below-trend growth for China and India," JBC Energy said in a report.

Still, positive data out of the United States, subsequent assurances by the U.S. Federal Reserve of continuing with its easy policy, and lingering worries of supply disruption from the Middle East may help push prices higher, Emori said.

Brent remains neutral in a range of $109.14 to $111.33 per barrel, while U.S. oil is expected to test resistance at $93.72, according to Reuters technical analyst Wang Tao.

Oil, particularly the U.S. benchmark, was supported by a report from the American Petroleum Institute (API) that showed U.S. crude inventories fell 1.4 million barrels last week. The market had been expecting a rise of 2.3 million barrels, according to a Reuters poll.

During the same week, gasoline inventories fell 3.1 million and distillates declined 2.2 million barrels, the API said.

(Additional reporting by Manash Goswami and Ramya Venugopal in Singapore; editing by James Jukwey)