Russian authorities have tightened security ahead of President Bush's arrival in Moscow later Thursday. This is the second stop on his six-day European tour.
Security has been increased at all major buildings in Moscow and Saint Petersburg, along with the international airports and border checkpoints.
Russian security services are also on the alert for attacks by rebels in separatist Chechnya to coincide with the Bush visit. Military officials say they have intelligence reports that rebels plan attacks in four Chechen cities including the capital, Grozny.
The highlight of the Putin-Bush summit will be the signing Friday of a new arms-reduction pact that will cut America's and Russia's long-range nuclear arsenals by two-thirds.
In an statement broadcast on Russian television in advance of the visit, Mr. Bush said it is important to show the world the United States and Russia are no longer enemies and that neither side is, as he put it, "clinging to our stocks of these terrible weapons." He said a new relationship is developing between the two countries.
Mr. Bush and President Putin have developed a warm personal relationship that analysts here say has gone a long way to improving ties.
And ever since the September 11 attacks on the United States, Mr. Putin has stood firmly behind the American-led war on terrorism.
There are a number of unresolved issues that stand in the way of even closer ties, however. Chief among them now is American concerns about possible nuclear technology transfers from Russia to Iran and other countries that Washington has described as rogue states.
Other problems involve Russian opposition to Mr. Bush's plan to develop a national missile system and trade issues, led by the U.S. decision to increase tariffs on certain steel imports and Russian restrictions on U.S. poultry imports.