Oil prices rose on Friday as the prospect of the US intercepting more Venezuelan oil tankers deepened supply concerns, but remained on track for a weekly decline amid optimism over a possible Russia-Ukraine peace agreement.

Brent crude futures rose 29 cents, or 0.5%, to $61.57 a barrel by 0115 GMT, and US West Texas Intermediate crude was at $57.91 a barrel, up 31 cents, or 0.5%.

The US is preparing to intercept more ships transporting Venezuelan oil following the seizure of a tanker this week, as it increases pressure on Venezuelan President Nicolas Maduro, six sources familiar with the matter said on Thursday.

The US seizure this week raised concerns about supply disruptions.

“After selling on expectations that supply pressures would ease amid hopes for a Russia-Ukraine peace agreement, buying emerged to pare losses following the US seizure of a Venezuelan tanker,” said Hiroyuki Kikukawa, chief strategist of Nissan Securities Investment, a unit of Nissan Securities.

“Peace negotiations between Russia and Ukraine will remain the main focus next week and beyond,” he said, noting that WTI could test the $55 level if a deal is genuinely reached.

A possible peace agreement between Russia and Ukraine would likely increase the supply of Russian oil that is currently sanctioned by Western countries.

The leaders of Britain, France and Germany held a call on Wednesday with US President Donald Trump to discuss Washington’s latest peace efforts to end the war in Ukraine, in what they said was a “critical moment” in the process.

But on Thursday, Ukrainian drones struck an oil platform in the Caspian Sea for the first time, halting production at the facility owned by Lukoil (LKOH.MM), opens new tab, according to an official from Ukraine’s Security Service.

Meanwhile, the International Energy Agency upgraded its 2026 global oil demand growth forecasts while trimming its supply growth predictions in its latest monthly oil market report on Thursday, implying a slightly narrower surplus next year.

The IEA flagged higher demand prospects due to a stronger world economy and lower supply from nations under sanctions.

But Organization of the Petroleum Exporting Countries (OPEC) data published on Thursday indicated that world oil supply will match demand closely in 2026, an outlook that contrasts with projections from the IEA and others of a huge glut.