Oil prices continued their climb today, hitting eight-month highs, as expectations of US crude draws underpinned a market already worried about potential supply shortages from attacks on Nigeria's oil industry.
US crude stockpiles likely fell by 3.5 million barrels last week to mark a third straight week of declines, a preliminary Reuters poll showed.
Trade group American Petroleum Institute is expected to cite a drawdown as well in its inventory report, before official stockpiles data slated for tomorrow from the US government.
Crude oil rallied in the past two sessions after rebels in Nigeria's Niger Delta vowed to halt output in the country, which until last year was Africa's biggest producer turning out about two million barrels per day (bpd).
The Nigerian government said it was initiating talks with the rebels.
"The market remains concerned about unscheduled supply interruptions with the latest coming from additional shut-ins in Nigeria," Dominick Chirichella, senior partner at the Energy Management Institute in New York, said.
"With the industry projecting a decline in total US crude oil stocks in this week's reports, the market bears are remaining on the sidelines."
Brent crude futures were up 55 cents at $51.10 a barrel by 5.20pm Irish time, after rising to $51.30 earlier, their highest since October.
US crude's West Texas Intermediate (WTI) futures gained 40 cents to $50.09, having touched a fresh 2016 peak of $50.37 earlier.
Both Brent and WTI have almost doubled in value since winter, when they hit their lowest since 2003.
Prices began recovering since end February on talk of an OPEC production freeze, which, however, did not materialise.
The rally heightened after last month's wildfires in Canada's oil sands region and also has been supported by supply outages elsewhere, including Nigeria, Venezuela and Libya.
The US Energy Information Administration said expects crude production declines for 2016 and 2017 to remain unchanged from a month ago.
Production will fall by 830,000 bpd this year to 8.6 million bpd, while drop next year by 410,000 bpd to 8.19 million bpd, the agency said in its short term energy outlook.
The EIA also said raised its 2016 US oil demand growth forecast by 220,000 bpd from a previous 140,000 bpd.