"The other [Russian] shareholders want to tear up the agreement that they willingly signed in 2003. We are not prepared to do that and will vigorously defend our rights using all legal means at our disposal," Tony Hayward told a news conference.
"We will not be intimidated by strong arm tactics," he said.
BP and its Russian billionaire partners in TNK-BP have been battling over management and strategy at the joint venture, which is Russia's third largest oil producer and accounts for a quarter of BP's overall output. The British oil major earlier said the Russian investors want to seize control of the company through "raider tactics."
TNK-BP CEO Robert Dudley left Russia last week citing a campaign of harassment by the Russian shareholders, who have sought his dismissal, accusing him of acting only in BP's interests. The U.S. executive said he would temporarily run the company from abroad.
The four Russian shareholders, who hold 50% via their AAR consortium, asked BP in a letter on Monday to disclose Dudley's whereabouts, saying his plan to run the firm from a country other than Russia could imply tax obligations to that country.
Hayward said Dudley is currently on holiday in Central Europe, and that his exact whereabouts will be made public in the next few days. He also said Dudley's management of the firm from abroad would have no tax implications for the company.
Dudley had also attributed his departure to the Russian authorities' failure to renew his work visa, as his transit visa was due to expire on Monday.
Hayward also said BP was set on finding a solution acceptable to both sides: "We cannot be sure how things will pan out in Russia but I can tell you that we're committed to trying to find a solution that's acceptable to all parties - whether that's possible we'll see."
