Saudi Arabia and Russia Tuesday announced fresh extensions to their voluntary supply cuts, spurring a 2% increase in oil prices.

The extension stretches a combined 1.3 million barrel per day (bpd) reduction for another three months through December.

Brent crude futures for November were up $1.44, or about 1.6%, to $90.44 a barrel by 1334 GMT, eclipsing the $90 level for the first time since last November.

Meanwhile, U.S. West Texas Intermediate crude (WTI) October futures rose $1.85, or about 2%, to $87.4.

Riyadh's decision to extend its 1 million bpd voluntary cut will be reviewed monthly to consider whether to deepen the cut or increase production, state news agency SPA said on Tuesday.

Saudi Arabia was widely expected to extend its voluntary cuts into October.

"This additional voluntary cut comes to reinforce the precautionary efforts made by OPEC+ countries to support the stability and balance of oil markets," the Saudi Press Agency report said, citing an unnamed Energy Ministry official.

The kingdom has been unilaterally cutting its output to try and boost sluggish crude oil prices.

Fellow OPEC+ member Russia also prolonged its voluntary cuts through the end of the year "to maintain stability and balance" on oil markets, Deputy Prime Minister Alexander Novak said on Tuesday.

The world's second-largest oil exporter is reducing exports by 300,000 bpd for the period. It has been cutting output and exports in tandem with Saudi Arabia on top of existing OPEC+ supply reductions.

Russia had said it would cut oil exports voluntarily by 500,000 bpd, about 5% of its output, in August and by 300,000 bpd in September. Russia is also reducing its oil production by 500,000 bpd until the end of 2024.

A series of production cuts over the past year has failed to substantially boost prices amid weakened demand from China and tighter monetary policy aimed at combating inflation.

The Saudis are particularly keen to boost oil prices to fund Vision 2030, an ambitious plan to overhaul the kingdom's economy, reduce its dependence on oil and create jobs for a young population.

The plan includes several massive infrastructure projects, including the construction of a futuristic $500 billion city called Neom.

Higher prices would also help Russian President Vladimir Putin fund his war on Ukraine. Western countries have used a price cap to try to cut into Moscow's revenues.

Western sanctions mean Moscow is forced to sell its oil at a discount to countries like China and India.