Rosneft boss Igor Sechin defiant over US sanctions
The chief executive of Russia's state-controlled energy giant, Rosneft, has said sanctions imposed on him by the US will not affect the company's trade.
Igor Sechin has been added to a list of individuals thought to be in Vladimir Putin's "inner circle", whose assets will be blocked in the US.
However, no sanctions were imposed against Rosneft itself.
British oil company BP, which owns almost 20% of Rosneft, said it would not sever ties with the Russian firm.
In a statement reported by the privately-owned Russian news agency Interfax, Mr Sechin was defiant, assuring Rosneft's shareholders and partners that "effectiveness" and "cooperation" would not be affected by the US announcement.
"I consider Washington's latest steps as high assessment of the effectiveness of our work," he added.
On Monday, US officials released a list of seven individuals and 17 companies that it said it was adding to its sanctions list.
The sanctions, which prevent US companies from engaging with those named, are in response to Russia's intervention in Crimea and Ukraine.
Those added to the sanctions list will have their US assets blocked and US citizens are generally prohibited from doing business with them.
BP remains 'committed'
BP, one of Rosneft's largest shareholders, said it would continue to work with the company, despite the sanctions.
"We are committed to our investment in Rosneft, and we intend to remain a successful, long-term investor in Russia," a BP spokesman said.
But, he added, the company was "studying today's announcement in order to understand what exactly it might mean for BP".
BP's share price fell on the news, ending the day down 1% at 488.35p.
However another oil giant, Shell, which often trades with Rosneft, said it would comply with US regulations.
Rosneft credit rating cut
In a separate announcement on Monday, Rosneft's credit rating was cut to "near junk" by Standard and Poor's.
The ratings agency downgraded Rosneft to a BBB- credit category, just one notch above "junk" status.
The agency had already cut Russia's overall rating to BBB- on Friday.