UPDATE 4-Oil flat, heads for weekly drop as rising crude supply weighs

* IEA sees 2018 global oil demand increasing by 1.5 mln bpd

Non-OPEC supply to rise by 1.8 mln bpd this year -IEA

* Coming up: Baker Hughes U.S. rig count data at 1 p.m. EDT (Updates prices, market activity, adds commentary; changes byline, dateline to NEW YORK, previously LONDON)

By Stephanie Kelly

NEW YORK, March 16 (Reuters) - Oil prices were little changed on Friday, set for a weekly decline on concerns that global crude supplies are rising despite efforts by OPEC and other producers to tighten the market.

U.S. West Texas Intermediate (WTI) crude futures remained unchanged at $61.19 a barrel by 11:00 a.m. EDT (1500 GMT). Brent crude futures dipped 11 cents to $65.01 a barrel, a 0.2 percent loss.

"Oil prices have lacked direction in today's session, as was the case yesterday, in the absence of new fundamental drivers," said Abhishek Kumar, Senior Energy Analyst at Interfax Energys Global Gas Analytics in London.

"Nevertheless, there is a downbeat bias as market participants focus on rising oil production in the U.S. and how it impacts effectiveness of the OPEC-led output-cut agreement."

On Thursday the International Energy Agency (IEA) said global oil demand is expected to pick up this year but supply is growing at a faster pace, leading to a rise in inventories in the first quarter of 2018.

The agency raised its forecast for oil demand this year to 99.3 million barrels per day (bpd) from 97.8 million bpd in 2017.

The IEA also said it expected supply from non-OPEC nations to grow by 1.8 million bpd in 2018 to 59.9 million bpd, led by the United States.

OPEC and other producers began cutting supply in January 2017 to erase a global crude glut that had built up since 2014.

Market participants will be looking ahead to U.S. rig count data due at 1 p.m. EDT on Friday.

"Producers, as we've gone through earnings, are showing that they're going to remain disciplined even with a little more supportive oil price, which we think is healthy for the market," said Matt Sallee, a portfolio manager at Tortoise Capital in Leawood, Kansas.

Sallee added that he expected the data to show a small pickup in rig counts.

On Wednesday, the U.S. government reported that crude stockpiles in the United States increased by a more-than-expected 5 million barrels, rising for a third straight week.

Political risk linked to Tehran increased after Rex Tillerson was sacked as U.S. secretary of state in favor of an Iran and North Korea hawk. Saudi Arabia's crown prince said Riyadh would develop nuclear weapons if Iran did so.

(Additional reporting By Julia Payne; Editing by David Gregorio)