Memo to Vladimir Putin: The Cold War is over.

President Bush gave the Russian president a firm response Tuesday to his remarks that Moscow would take "retaliatory steps" if the U.S. went ahead with plans to build a missile defense system in Europe.

"Russia is not the enemy," Bush said after meeting with Czech President Vaclav Klaus and Prime Minister Mirek Topolanek. "The Cold War is over. It ended."

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Despite frostier relations with the man whom Bush once felt so chummy with that he nicknamed him "Pootie-Poot," the president offered an olive branch to the Kremlin — one he says he will deliver personally to Putin later this week on the sidelines of the Group of Eight summit in Germany.

"My message will be: 'Vladimir — I call him Vladimir — you shouldn't fear a missile defense system. As a matter of fact, why don't you cooperate with us on a missile defense system?"' Bush said.

Bush said the system would be coordinated with NATO. He said he would urge Putin to participate. "Please send your generals over to see how such a system would work. Send your scientists," Bush said.

U.S. experts contend the shield poses no threat to Russia because the missiles involved would be purely defensive and incapable of being fitted with warheads.

The president appeared with his hosts in a high-ceilinged hall of Prague Castle. The Czech president said it was significant that Bush promised to make "maximum efforts" to explain his position to Putin.

"We have pointed it out to our guest that it is very important that we win maximum support for this project of the Czech Republic who are very sensitive to those issues," Klaus said. "I suppose this is what President Bush clearly realizes."

Topolanek endorsed the plan as well.

The White House has billed a speech Bush will deliver on democracy at Czernin Palace as the highlight of his visit. Bush was invited to make the speech as part of a conference on democracy hosted by Natan Sharansky, a former prisoner of the Soviet regime who has continued to champion freedom, and former Czech President Vaclav Havel, who led the Velvet Revolution that ended communism in the former Czechoslovakia in 1989. The president also plans to meet with current and former dissidents from around the world.

From Prague, Bush will travel to Germany's Baltic Sea resort town of Heiligendamm for three days of meetings between the leaders of the world's eight major industrialized democracies. The rest of his eight-day European trip was to include a stop in Poland — also a proposed site for part of the missile defense system — as well as visits to Italy, Albania and Bulgaria.

The Associated Press contributed to this report.

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