By Ayenat Mersie
Brent crude oil futures were down 9 cents at $71.33 a barrel by 11:50 a.m. EDT (1550 GMT), having come off an earlier high of $71.89, while U.S. crude futures slipped 8 cents to $66.14.
"We're starting to see a little of the premium come off from geopolitics, and the focus is shifting to inventories," said Bill Baruch, president of Blue Line Futures in Chicago.
Brent has risen 1.4 percent so far this month. It hit a peak last week of $73.09, the highest since late 2014, amid mounting tensions in the Middle East, the possibility of renewed U.S. sanctions against Iran and falling output in Venezuela, where economic crisis has dragged down oil output to multi-year lows.
"The rally upwards was purely on geopolitical risk and if now we haven't had any further stimulus, we're seeing prices slip off a bit," Natixis commodities strategist Joel Hancock said.
Analysts expected uncertainty over U.S. policy towards Iran to continue to support prices through May 12, the deadline that U.S. President Donald Trump gave to Congress and European allies to "fix" the Iran nuclear deal.
If Washington does not renew sanctions relief for Tehran at this point, Iran may have difficulty exporting its crude.
Healthy demand and coordinated crude supply cuts by the Organization of the Petroleum Exporting Countries and several partners including Russia have made oil one of the top-performing commodities of 2018, with a gain of 7 percent, after wheat and corn, which have gained nearly 10 percent.
Bullish enthusiasm over the outlook for oil prices, however, might be contained by an increase in supplies in Cushing, Oklahoma, the delivery point for U.S. crude futures.
"We've seen that front May-June spread in WTI swing back into contango today. And that's somewhat of a bearish...it implies a continued up trend in Cushing crude supply," said Jim Ritterbusch, president of Ritterbusch and Associates in Galena, Illinois.
"There's not much volatility today, as we wait for API and EIA data," Ritterbusch said.
The American Petroleum Institute publishes weekly U.S. fuel inventory data later on Tuesday, while official government data, including on production, is due from the EIA on Wednesday.
(Additional reporting by Amanda Cooper in London; Henning Gloystein in Singapore; Editing by David Evans and Bernadette Baum)
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)