LONDON, July 29. /ITAR-TASS/. Further sanctions against Russian oil giant Rosneft could have a “material adverse” effect on its finances and operations with British oil and gas company BP, which owns almost 20% of Rosneft, BP said on Tuesday.

“If further international sanctions are imposed on Rosneft or new sanctions are imposed on Russia or other Russian individuals or entities, this could have a material adverse impact on our relationship with and investment in Rosneft, our business and strategic objectives in Russia and our financial position and results of operations,” the group said in a statement accompanying its second-quarter results.

State-controlled Rosneft, which accounts for 40% of Russian oil production, was hit by sanctions from the United States over Ukraine, limiting the company's access to Western money. Targeted assets included Rosneft’s stake in Ruhr Oel GmbH (ROG), a joint refining and marketing company, of which Rosneft and BP each owns 50%. The joint venture has stakes in four refineries in Germany - Gelsenkirchen, MiRO, Bayernoil and PCK Schwed, accounting to about a fifth of Germany's refining sector capacity.

“These sanctions have no strong impact on BP and ROG yet,” the British company said, adding that it would continue to mnitor the situation.

Vladimir Buyanov, a BP spokesman in Russia, said in mid-July the company was taking a look at the potential impacts of US. sanctions.

“We are currently looking into new sanctions the United States has imposed on Russia,” Buyanov told ITAR-TASS.

On July 17, the White House announced new “sectoral” sanctions against Russia, targeting some of the country’s largest energy corporations and banks as punishment for Moscow’s alleged reluctance to curb violence in Ukraine.

The targets of the US sanctions include two major Russian energy firms: Novatek, the country's largest independent natural gas producer, and Rosneft, Russia's major petroleum company and third largest gas producer. The penalties bar both from getting long-term loans from US entities.

Also targeted were leading Russian financial institutions: Russian development bank VEB and Gazprombank, banking arm of Russia's state energy giant Gazprom. The sanctions ban them from access to US capital markets.

A BP spokesman in London said the sanctions appeared on first glance to focus on restricting access of targeted firms to medium and long-term US financing.