There has been a similar shift in joint ventures between Russian and Western companies.
A decade ago, dozens of projects were planned but the number has shrunk to just a few ventures, which are important but not critical to help Russia maintain its output growth.
U.S. oil giant Exxon Mobil and Italy's Eni, for example, have dropped plans to help Russia develop offshore fields and U.S. company ConocoPhillips sold out from Russia's biggest private oil firm Lukoil.
The key remaining ventures involving Western companies are three projects between BP and Rosneft in East and West Siberia and a gas venture between Rosneft and Exxon Mobil on Sakhalin island.
Also on the gas front, Royal Dutch Shell and France's Total have been considering new liquefied natural gas projects with Gazprom and Novatek, as well as a new pipeline to Europe under the Baltic Sea.
But to put the projects in perspective, the combined cost of all of them is about $50 billion - less than a 10th of the Russian oil industry's investment programme for the next decade.
And if Western institutions are wary of lending to Russia, other countries such as China have been prepared to step in. Novatek and Total, for example, launched the $27 billion Yamal LNG plant this year with Beijing's financial support.
The weakest link in the Russian oil industry in the face of sanctions has traditionally been high-end Western technology such as complex drilling, hydraulic fracturing or IT, said Denis Borisov, director of EY's oil and gas centre in Moscow.
Russia's drilling and oil servicing market is worth about $20 billion a year and the share of the market held by Western service companies has remained fairly steady over the last few years and at about a fifth.
"But the process of replacing foreign equipment with local production has gathered pace," said Borisov.
Rosneft, which produces 40 percent of Russian oil, has recently tested its own simulated hydraulic fracturing technology - the extraction technique that spurred the boom in U.S. shale oil production.
The technology first came to Russia mainly via major Western oil services firms such as Schlumberger and Halliburton .
Companies such as Schlumberger are still doing a lot of complex drilling work in the Caspian Sea and West Siberia for Lukoil, as well as working on the world's longest extended reach well for Exxon and Rosneft off the Sakhalin island.
But Fitch's Marinchenko said the reliance of Russian oil firms on Western technology has declined since 2014 thanks to imports from China and local production of drilling equipment.
Since 2014, Rosneft's own drilling subsidiary has doubled its market share to 25 percent, meaning the company has become almost self sufficient.
"It is clear that new wide-scale sanctions on technology will not become the start of an end for the Russian oil industry, especially if Europe doesn't join them," said Marinchenko. "But it will complicate the development of hard to extract or depleted deposits."
