MOSCOW — Russian President Dmitry Medvedev echoed his predecessor, Vladimir Putin, in a gritty foreign policy speech Tuesday, vowing to respond if Washington places missiles in Central Europe.

He also promoted an idea he already has made a hallmark of his two-month-old presidency — calling for a new European security treaty he claims would remove the divisions Russia says that NATO has created.

Medvedev, Putin's hand-picked successor, signaled that Russia would not back down on a series of disputes with the West and in particular the United States.

He called Kosovo's Western-backed independence declaration a "sad" episode that violated international law and said the proposed deployment of U.S. missile defense facilities in former Soviet satellites in central Europe would undermine security.

"We will be forced to adequately react to this. Our American and European partners have been warned," Medvedev said in a speech to Russian ambassadors.

The United States wants to place a tracking radar in the Czech Republic and missile interceptors in Poland. Russia says it is not convinced by U.S. insistence that the shield is meant to neutralize a potential Iranian threat and suspects the true aim is to weaken Russia's nuclear deterrent.

Medvedev did not specify the nature of the response, but in February then-President Putin said Russia could aim missiles toward prospective missile defense sites and deploy missiles in the Baltic Sea region of Kaliningrad, which borders Poland, if the U.S. plan went forward.

Medvedev's address coincided with his approval of a Foreign Policy Concept setting out the fundamentals of Russia's external relations strategies.

The document, posted on the Kremlin Web site, underscored that Russia "continues to disapprove of NATO expansion" into Georgia and Ukraine, two former Soviet republics whose pro-Western leaders have angered Moscow by courting the West.

Medvedev added in broader terms that the architecture of international relations should be re-examined — a suggestion that the U.S. clout should be diminished.

"We are really worried by the fact that there is still no modern collective security system that would be open for all," Medvedev said.

"The experience of recent years, especially in Iraq and the Middle East, shows that today's global problems cannot be resolved through the direct use of force," he said. "We need reform of international institutions and a strengthened role for the United Nations. This position of ours remains unchanged."

Medvedev's call for Russian diplomats to avoid confrontation in defending the country's interests may have hinted at a change in style from Putin, who often took an imposing tone in disputes with the West. But he signaled no change of position on any issue.

The Foreign Policy Concept echoed Medvedev's speech and also recommended increased state support for Russian media abroad to help ensure the country is "perceived objectively."

The Foreign Policy Concept, which was approved by Putin after his first election in 2000, also called for a greater role for the U.N. and criticized NATO.

Medvedev won a March presidential election in which he was assured of victory by the support of Putin, who is now prime minister. Putin was absent from the address, which was attended by most Cabinet ministers at Russia's Foreign Ministry headquarters.