MOSCOW - British Prime Minister Tony Blair praised Russian President Vladimir Putin on Thursday for his role in building an international anti-terrorism front.

"We would like to pay tribute to your leadership which is of immense importance in bringing together a coalition against terrorism," Blair told Putin as he arrived in Moscow at the start of a trip to bolster support for possible military action in Afghanistan.

"The fact that we have a unified response to the terrible events of 11th September indeed shows that the world is coming closer together."

Putin, who describes separatists in Russia's southern region of Chechnya as "terrorists", was among the first world leaders to support the U.S. idea of forming a coalition to fight international terrorism after the September 11 hijack attacks in the United States left nearly 6,000 people dead or missing.

Putin has also backed U.S. commitment to hunt down Saudi-born dissident Osama bin Laden, whom Washington blames for masterminding the attacks, along with the Taliban rulers of Afghanistan, who are hiding bin Laden.

Russia has promised to exchange information with the United States and to provide an air corridor for U.S. planes with humanitarian goods. Russia has also offered support to Afghanistan's Northern Alliance as its contribution to the joint fight.

More significantly, Russia has told its Central Asian allies bordering Afghanistan that they can negotiate separately their participation in the planned U.S. attack.

Blair is expected to leave Moscow early on Friday for Pakistan, after which it is thought he will visit the Gulf state of Oman, where some 20,000 British troops are holding long-planned military exercises.

"This is part of the coalition-building process and Russia is important in that regard, not least because of its wider interests across the region," Blair's spokesman told reporters earlier.

U.S. Defense Secretary Donald Rumsfeld visited Oman on Thursday, after a 15-hour visit to Saudi Arabia.

Putin visited Brussels earlier in the week, where he met NATO Secretary-General George Robertson and European Union officials.