Six years after Rosneft marked a new high watermark in US-Russian corporate relations by agreeing a co-operation deal with ExxonMobil, the Kremlin-controlled oil company has found alternate support from the east. CEFC China Energy agreed last month to pay $9.1bn for a 14.16 per cent stake in Rosneft — and it is not the only Russian company to find new friends in China.

Chinese companies are snapping up stakes and signing joint venture agreements across Russia’s energy sector. And they have competition — Saudi Arabia’s new-found political friendship with Russia has started yielding corporate agreements, too.

Hit by US and EU sanctions after its 2014 invasion of Crimea, Moscow has turned to Beijing for friendship and finance. Assistance was both necessary and geopolitically expedient: New York and London are not the only places with banks, went the message. Then when oil prices fell to historic lows two years later, cutting a deal with Saudi — the world’s other crude-exporting superpower — to reduce production helped reverse the slide and ease struggling fiscal budget calculations.

But while sanctions may have prompted the agreements, business realities help explain Chinese and Saudi corporate partnerships. For Chinese energy companies, Russia offers both vast resource supply and handy proximity. For Saudi Aramco, the Kingdom’s state-owned hydrocarbon giant, Russia offers potential partners struggling with the same existential business quandaries — how to extract more for less, and tackle the threat of alternative energy sources.

China needs energy and power to fuel its growth, and shares a 4,200km border with Russia. For the Russians, having a major customer in the east makes good business sense: oil and gas from fields in the far east would need to be pumped across as many as 11 time zones and 7,000km worth of frozen tundra, forests and mountains to reach Europe. China is next door and, as a bonus, has cash to invest in capex-heavy drilling projects.

Over the past 18 months, Chinese companies have spent more than $14bn on Russian energy projects. China now owns stakes in Russia’s largest oil company, petrochemical group and gold producer. By next month, CEFC will add a $500m investment in energy-to-aluminium business EN+ as part of the company’s $1.5bn listing in the London. “The Chinese think long-term, they think very strategically,” said a person involved in one of the investments. “They want access to the resources, but they are also thinking about partnerships that will last decades.”

In Riyadh, energy executives share the same fears as their opposite numbers in Moscow. A future world of $50-a-barrel crude prices means drilling, pumping and refining must become more efficient and less expensive. It is no surprise that one of dozens of corporate agreements signed during King Salman bin Abdulaziz’s state visit to Moscow last week was for Aramco and Gazprom Neft, the oil arm of Moscow-controlled gas monopoly Gazprom, to collaborate on research and development.

“This is just the beginning,” said Ibrahim Al-Omar, governor of the Saudi Arabian General Investment Authority. “We are [in Russia] to meet people, to shake hands, to find all the ways in which companies from our two countries can work together,” he said. “There is vast potential.”

Three years ago, western sanctions imperilled the Arctic LNG project in Russia’s northern Yamal peninsula owned by Russia’s Novatek and France’s Total. Chinese finance came to the rescue with a $12bn package. Today, Russian officials are keen for Saudi companies to play their part in a second iteration of the project, Nord Stream 2. The gas pipeline to Europe is being built by Gazprom, but five EU energy companies have agreed to finance half of its cost.