NEW ORLEANS -- BP's mounting costs for capping and cleaning up the Gulf of Mexico spill have reached $2.65 billion, it said Monday, but the oil giant denied reports out of Russia that CEO Tony Hayward is resigning.

The company's expenses climbed to $100 million per day over the weekend, according to an SEC filing Monday, as engineers eyed a tropical storm headed for the Texas-Mexico border.

It was a rocky start to the week after BP PLC stock fell 6 percent Friday in New York to a 14-year low. BP has lost more than $100 billion in market value since the deep-water drilling platform it was operating blew up April 20, killing 11 workers and starting the massive leak that has fouled the coastline in four states.

British-based BP rushed to deny the report by Russia's state RIA Novosti news agency, which said a senior Russian Cabinet official had said Hayward was expected to resign as chief executive officer.

It quoted Deputy Prime Minister Igor Sechin, before a Moscow meeting with Hayward on Monday, as saying that Hayward would introduce his successor.

BP spokeswoman Carolyn Copland in London said the report "is definitely not correct." Sheila Williams, also in London, said, "Tony Hayward remains chief executive."

"They are mistaken," U.S.-based BP spokesman Mark Proegler said of the Russian report.

After the meeting, a spokesman for Sechin said Hayward's resignation wasn't discussed. Spokesman Rustam Kozharov said topics included the Russian joint venture TNK-BP, which accounts for about a quarter of BP's reserves and production.

Moscow-based oil analyst Konstantin Cherepanov from the Swiss investment bank UBS said that he gave little credence to reports of Hayward's resignation.

"I'm sure there has been a misunderstanding. Hayward's resignation at this time and in this place lacks logic," he said.

"It would make sense that Hayward would finish his job tackling with the oil spill and step down afterwards so that the new CEO wouldn't have his burden on his shoulders."

In a filing Monday to U.S. securities regulators, BP said the cost of its response to the Gulf of Mexico oil spill had reached about $2.65 billion, up from $2.35 billion as of Friday.

BP said it had received more than 80,000 claims and made almost 41,000 payments, totaling more than $128 million.

The rig drilling the relief well that's the best hope of stopping the oil spill has made it within about 20 feet horizontally of the blown-out well that's gushing crude, BP Senior Vice President Kent Wells said Monday.

Wells said the rig is going to drill an additional 900 feet down before crews cut in sideways and start pumping in heavy mud to try to stop the flow from the damaged well. It's currently about 16,770 feet down.