Brent futures gained 1 cent, or ‌0.1 per cent, to $87.08 a barrel

Oil prices inched up on Friday after the US threatened an indefinite naval blockade of Iran, reviving concerns about ​supply of crude after the previous session’s decline on a weaker ​outlook for demand and a large build in US stocks.

Brent futures gained 1 cent, or ‌0.1 per cent, to $87.08 a barrel by 0247 GMT.

The benchmark was on track for weekly rises of around 4 per cent after the prior session’s drop of more than 2 per cent, paring gains following Brent’s six-session rally.

Despite the bearish crude stock data, the broader geopolitical backdrop is preventing a sharper price decline, Susan Bell, senior vice president for oil commodity markets at Rystad Energy said in a note.

On Thursday, the US warned that it could maintain a naval blockade of Iran indefinitely and ramp up economic pressure on Tehran as ceasefire talks have stalled.

The latest US threats come as Iran curbs traffic through the Strait of Hormuz, which carried 20 per cent of the world’s oil before the war, driving up fuel prices and putting pressure on US president to end the war.

The prospect of a longer war constraining supply was offset this week by forecasts from OPEC and the International ​Energy Agency lowering outlooks for demand growth, while data showed the largest weekly gain in US crude stocks for more than 3-1/2-years.

KCM chief market analyst Tim Waterer said the two forces were acting as counterweights.

He said: The result is a market that remains supported but struggles to break meaningfully higher while these opposing pressures ​remain in place.