RIYADH: Oil prices headed for their longest streak of weekly gains since October as freezing weather across North America threatened oil supplies in a market already concerned about disruption from a potential war in Ukraine.

Brent crude gained 1.4 percent to $92.36 at 1:55 p.m. Riyadh time, following a similar-sized advance on Thursday — the highest since September 2014 and puts it on course for a seventh straight weekly increase. 

US benchmark WTI added 1.5 percent to $91.58 after a $2 surge on Thursday saw it settle above $90 for the first time since October 2014.

Brent and WTI futures were up by about 19 percent and 22 percent, respectively, so far this year.

“Crude surged over the $90 level after an Arctic blast made its way to Texas and disrupted some oil production in the Permian Basin,” said Edward Moya, senior market analyst at OANDA.

Central and Eastern parts of the US and Canada have been hit by blizzards and heavy snowfall, grounding flights, closing roads and causing power cuts for thousands. More than 91 million people are under a winter weather warning or advisory. 

The storm has already produced more than three feet of snow in one part of New Mexico and more than a foot across several Midwestern states.

“Even as thousands of flights are cancelled, the energy market is fixated over production and not so much short-term demand shocks,” said Moya.

The Organization of the Petroleum Exporting Countries and its allies led by Russia, known collectively as OPEC+, agreed earlier this week to stick to a plan to increase output by 400,000 barrels per day, but some members are already struggling to meet quotas, leaving consumers frustrated.

Tight oil supplies have pushed the price of oil deliverable in six months close to an eight-month high of $8.15 above spot prices, a phenomenon called backwardation. Such price structures usually encourage buying of oil from storage in the expectation that future prices are going to be higher than today’s.

Oil prices have been pushed up by simmering tension in Eastern Europe where Russia has amassed thousands of troops on the border with Ukraine amid warnings by the US and others of a potential invasion.

The US warned on Thursday that Russia was planning to use a staged attack as justification for invading Ukraine. Russia’s President Vladimir Putin has blamed NATO and the West for increased tensions.

“With geopolitical risk in Ukraine and only gradual increase of production by OPEC+, prices are expected to head toward $100 a barrel,” said Chiyoki Chen, chief analyst at Sunward Trading.

However, some analysts are pointing to a possible change in market dynamics in the coming months as supply begins to outpace demand.

“We expect the sequential trend of quarterly global stock draws will flip to inventory builds as soon as 2Q’22, and sustain for the next 15-18 months,” said analysts at Citi Research.