In an interview with the Financial Times, published on Monday, Hayward said that cutting off capital markets from Russia's energy groups, which would eventually lead to less investment in Russian oil production, was likely to damage long-term supply.
He said the US shale boom had obstructed the growing risks to the world’s supply picture, but its effect would wear off, leaving the global economy dangerous exposed to potential disruption in the flow of oil, the daily cited him as saying, adding his comments came as the US and Europe expanded sanctions against Russia on Friday with the US adding Gazprom, the leading energy provider for Europe, and the Lukoil oil group to the list of companies deprived of US goods, technology and services for deepwater, Arctic offshore and shale projects. EU and US sanctions have also imposed restrictions on financing for some state-owned Russian energy companies.
Russian future production from untapped resources in the Arctic and the vast shale reserves of Siberia are under threat because of sanctions, Hayward said.
"Because of financial sanctions, the big gorillas [major oil companies] are going to start cutting their activities," he added.