WASHINGTON – Russia is threatening to revoke BP’s license to exploit a giant natural gas field in Siberia, stirring fresh fears among foreign investors over Kremlin intervention in Russian business affairs.

The threat to pull the company’s license to tap the Kovytka field, which holds an estimated 2 trillion cubic meters of gas, has come as a shock to the British oil major and is being related by analysts to the Kremlin’s increasing efforts to tighten its grip on the country.

According to Russia’s resources minister Yuri Trutnev, the license may be withdrawn because BP and its Russian partner TNK had failed to build a local pipeline network. Mr. Trutnev said a decision would be made by next month.

But analysts say that is an excuse, arguing that the Kremlin wants to secure a bigger piece of the Kovytka project for the Russian energy giant Gazprom.

A spokeswoman for TNK-BP said the company had not been contacted directly by the Russian authorities. She added: “We have never received any formal notification of irregularities in the license conditions.”

“Gazprom is trying to muscle in,” said an oil analyst at Renaissance Capital, Adam Landes. Gazprom currently has a limited marketing role in the Kovytka field, but it has made no secret of its eagerness to participate on the production side.

Earlier this week, Russian President Putin backed a major shake-up that would see the state take a majority stake in Gazprom by merging it with the state-owned oil firm Rosneft. Foreign investors in Russia welcomed that move as state control had been made by the Kremlin a precondition for foreigners to purchase domestic Gazprom stock and the merger proposal was seen as an opportunity for foreign investors.

But any moves to strip BP of its Kovytka license would dampen enthusiasm for the Gazprom-Rosneft merger and would add to growing fears about the lack of predictability in Kremlin decision-making.

Those fears have been running high since the Kremlin last year launched an aggressive tax probe into Russian oil giant Yukos. The investigation has been widely interpreted as retaliation against Yukos’s former chief executive, Mikhail Khodorkovsky, for supporting Russian opposition politicians. Mr. Khodorkovsky, once Russia’s richest man, is in jail on fraud and tax charges.

BP’s chief executive, John Browne, last month sought personal assurances from the Kremlin that the TNK-BP partnership was secure and would not be affected by the Yukos affair. He told the British press on his return from a visit to Moscow that he received confirmation that BP’s presence in Russia is “decidedly welcome.”

Shortly after there were reports in the Moscow press that Russia’s secret service was investigating TNK-BP and that Mikhail Fridman, one of BP’s local partners, was also at the center of a probe.

TNK-BP is scheduled to start delivering gas from Kovytka to the Russian market by 2006 and to some neighboring countries in 2008.

BP signed an $8 billion partnership with TNK last summer in a deal that was described by the Financial Times as “one of the boldest and possibly long-sighted deals of the past two years” in the international energy field. Kovytka is the biggest project in the partnership. Mr. Browne admitted the deal could be risky and he observed when the deal was signed “in business, trust is never 100 percent.”