Oil prices slid today after Chinese data showed that demand from the world's largest crude importer remained lacklustre in September as strict Covid-19 policies and fuel export curbs depressed consumption.

Brent crude futures for December settlement were down $1.17, or 1.3%, at $92.33 a barrel this afternoon, after rising 2% last week.

US West Texas Intermediate crude for December delivery was at $83.65 a barrel, down $1.40, or 1.7%.

Although higher than in August, China's September crude imports of 9.79 million barrels per day were 2% below a year earlier, customs data showed today, as independent refiners curbed throughput amid thin margins and lacklustre demand.

"The recent recovery in oil imports faltered in September," ANZ analysts said in a note.

They added that independent refiners failed to utilise increased quotas as ongoing Covid-related lockdowns weighed on demand.

Uncertainty over China's zero-Covid policy and property crisis are undermining the effectiveness of pro-growth measures, ING analysts said, even though third-quarter gross domestic product growth beat expectations.

Brent rose last week despite US President Joe Biden announcing the sale of a remaining 15 million barrels of oil from the US Strategic Petroleum Reserves, part of a record 180 million-barrel release that began in May.

Biden added that his aim would be to replenish stocks when US crude is around $70 a barrel.

But bank Goldman Sachs said the stocks release was unlikely to have a large impact on prices.

US energy firms added oil and natural gas rigs last week for the second week in a row as relatively high oil prices encourage firms to drill more, energy services firm Baker Hughes said in a report.