* Brent futures at highest since November 2014
* Global inventories expected to fall further
* OPEC cuts and looming U.S. sanctions on Iran lift Brent
* Shell halts exports from major Nigerian pipeline (Updates throughout, changes dateline, previously LONDON)
By Jessica Resnick-Ault
NEW YORK, May 17 (Reuters) - Oil prices climbed above $80 a barrel on Thursday for the first time since November 2014, hitting new multi-year highs on concerns that Iranian exports could fall because of renewed U.S. sanctions, reducing supply in an already tightening market.
The market continued to push higher as geopolitical concerns drove trading.
"We are going to have reduced supplies from Iran in six months and Venezuela hasn't shown that they can stop the drop in their supplies," said Gene McGillian, vice president of research at Tradition Energy."
Brent crude futures reached an intraday high of $80.33 a barrel before receding to $80.16 by 11:09 a.m. EDT [1509 GMT].
U.S. West Texas Intermediate (WTI) crude futures were up 41 cents at $71.90 after also hitting their highest since November 2014, at $72.30 a barrel.
U.S. President Donald Trump's decision this month to withdraw from an international nuclear deal with Iran and revive sanctions that could limit crude exports from OPEC's third-largest producer has boosted oil prices.
France's Total warned on Wednesday that it might abandon a multibillion-dollar gas project in Iran if it could not secure a waiver from U.S. sanctions, casting further doubt on European-led efforts to salvage the nuclear deal.
A rapid decline in Venezuela's crude production has further roiled markets in recent months.
"The geopolitical noise and escalation fears are here to stay," said Norbert Rücker, head of macro and commodity research at Swiss bank Julius Baer. "Supply concerns are top of mind after the United States left the Iran nuclear deal."
Global inventories of crude oil and refined products dropped sharply in recent months owing to robust demand and OPEC-led production cuts.
Oil stocks were expected to drop further as the peak summer driving season nears, offsetting increases in U.S. shale output, Bernstein analysts said.
Several banks have in recent days raised their oil price forecasts, citing tighter supplies and strong demand.
Further supporting prices, Royal Dutch Shell on Thursday said it was halting crude exports from a major Nigerian pipeline.
On the flip-side, however, high oil prices could hit consumption, the International Energy Agency warned on Wednesday as it lowered its global oil demand growth forecast for 2018 to 1.4 million barrels per day (bpd) from 1.5 million bpd.
The IEA said global oil demand would average 99.2 million bpd in 2018, although U.S. bank Goldman Sachs said consumption would cross 100 million bpd "this summer".
Leading production increases is the United States, where crude output C-OUT-T-EIA has soared by 27 percent in the last two years to a record 10.72 million bpd, putting it within reach of top producer Russia's 11 million bpd.
The result has been a widening difference between U.S. crude and benchmark Brent. WTI traded at $8.20 a barrel below Brent on Thursday, the most since April 2015.
Additional reporting by Henning Gloystein in Singapore and Ron Bousso in London; Editing by Dale Hudson and David Goodman