Russia has fired another shot in what is fast becoming a new Cold War, condemning the successful American test of its missile defense shield — President Reagan’s Star Wars program — by threatening a full-scale arms race with the West if American weapons are stationed in space.

The dispute sets the scene for a tense encounter with President Sarkozy of France, who meets President Putin on Tuesday, and a Russo-American summit in Moscow next month between the Russian foreign and defense ministers and Secretary of State Rice and Defense Secretary Gates.

The American visit is intended to calm Mr. Putin’s fears over plans for the siting of NATO missile shield radar sites and interceptor missiles in the Czech Republic and in Poland.

“We don’t want to fight in space, but on the other hand, we’ll not allow any other country to play the master in outer space. The consequences of positioning strike forces in orbit will be too serious,” the commander of Russia’s space forces, Colonel General Vladimir Popovkin said in an interview with the Russian newspaper Trud yesterday.

On Tuesday, the Pentagon announced the successful test late last week of the missile defense network, which simulated a missile attack from North Korea. A dummy warhead was launched from a military base in Kodiak, Alaska, and was tracked by radar for 24 minutes before an interceptor missile launched from Vandenberg Air Force Base in California destroyed its target after a seven-minute flight.

“Does the system work? The answer is yes,” an Air Force lieutenant general, Henry Obering III, director of the Missile Defense Agency, told reporters.

The test was considered an important new fact in arguments about the feasibility of erecting a missile shield system on Europe’s eastern border, abutting Russia. Aware that the missile shield has severely aggravated European relations with Russia, European members of NATO have expressed doubts to America about the effectiveness of the system.

In “conversations with our European partners and allies and NATO partners in the past, one of the questions I do get asked is, ‘Well, this system is not proven. It doesn’t work, right?'” General Obering said. “I think this goes a long [way] to answering that question.”

Mr. Putin has railed against the NATO plans, which, despite American assurances that the shield is solely designed to protect against missiles launched by Iran and other rogue Islamist states, he believes are designed to threaten Russia at close quarters. To the alarm of many European foreign ministers, Mr. Putin has served notice that unless the shield is abandoned, Russia will pull out of a treaty limiting conventional forces in Europe.

The missile shield is just the latest in a series of incidents in which Russia, boosted by its revenue from oil stemming from the worldwide rise in energy prices, has adopted hostile positions against America and the Europeans. Mr. Putin has built his popularity on flexing Russian muscles on the world stage in an attempt to restore some of the influence on events his country enjoyed when the Soviet Union was one of the world’s superpowers.

Mr. Putin’s challenges to the expansion of NATO and the European Union into the former Warsaw Pact republics have caused a fracture among Europe’s leaders and made the prospect of a common E.U. foreign policy more distant. Mr. Putin has made it clear that he does not approve of former Soviet satellites Ukraine, Belarus, and the countries in the Caucasus joining the European Union or NATO.

Bellicose rhetoric from the Kremlin has been matched by specific actions designed to undermine American and European efforts on the international stage and frustrate those who would become allies of the West.

Two days after a majority of Ukrainian voters opted for the pro-Western Orange parties, Russia again threatened to cut off oil and natural gas supplies to Western countries, serving notice on Ukraine that it should not upset its eastern neighbor.

After a dispute surrounding the relocation of a Russian war memorial in the capital of the former Soviet client state Estonia, Tallinn, Russia was blamed for an orchestrated “cyber attack” in April on Estonia’s technological infrastructure, which severely disrupted Internet traffic.

Having at first supported American efforts to prevent Iran’s nuclear weapons program, Mr. Putin has changed his mind, informing the West that he will not agree to stronger sanctions in the United Nations against the mullahs’ regime while also ruling out Russian support in the U.N. Security Council for military action.

He also has reneged on what was thought to be an agreement among America, the European Union, Serbia, and Russia, to allow a former province of Yugoslavia, Kosovo, its independence from Serbia in December.

Routine flights of Russia’s nuclear bombers resumed this summer, prompting NATO fighters in Britain to scramble as the planes buzzed British and Norwegian airspace. Russia also enjoyed a propaganda success last month when it exploded one of the largest non-nuclear “bunker buster” bombs ever produced.

The Kremlin also has declined to repatriate to Britain the principal suspect in the murder by polonium poisoning in London of a Russian dissident former spy, Alexander Litvinenko.