MOSCOW - Russian President Vladimir Putin has sent a letter to world leaders accusing neighboring Georgia of harboring Chechen rebels and international terrorists and outlining his case for taking military action to end cross-border attacks, the president's press service said Thursday.

In the letter sent to U.N. Secretary-General Kofi Annan, U.N. Security Council members, and members of the Organization for Security and Cooperation in Europe ahead of the U.N. General Assembly meeting in New York, Putin accused Georgia of violating U.N. anti-terrorism resolutions and said Russia would take "adequate measures" to defend itself if Georgia did not act to quell the threat.

"If the Georgian leadership doesn't take concrete actions to destroy the terrorists, and bandit incursions continue from its territory, Russia will take adequate measures to counteract the terrorist threat, in strict accordance with international law," Putin said in the letter, which was released in Moscow on Thursday by the presidential press service.

Putin made his case against Georgia as world leaders gathered for a U.N. General Assembly meeting in New York, a day after the anniversary of the Sept. 11 terror attacks in the United States. U.S. President George W. Bush was due to address the assembly, presenting his case against Iraq, which he has called part of an "axis of evil."

In his letter, Putin said the "successful anti-terrorist operation" in Chechnya had driven "remaining fighters" onto Georgian territory, where they operate freely and continue to receive military and financial assistance. He said Georgia had rejected numerous Russian offers to conduct joint operations to root out rebels, and he criticized the recent Georgian security sweep through the Pankisi Gorge, which borders Chechnya, saying it had failed to achieve "concrete results" in eliminating the terrorist threat.

Putin said any Russian action in Georgia would not be "directed at undermining the sovereignty and territorial integrity of the country," or "changing the political regime."