Updated 9:10 a.m. ET
The Obama administration is shelving a European missile defense plan that has been a major irritant in relations with Russia, a U.S. ally said Thursday. The Pentagon confirmed a "major adjustment" is planned.
Jan Fischer, the prime minister of the Czech Republic, one of two countries where the system was to be built, told reporters that Obama phoned him overnight to say "his government is pulling out of plans to build a missile defense radar on Czech territory."
Without giving specifics, Pentagon spokesman Geoff Morrell said, "We have made a major adjustment and enhancement to our European missile defense system that will better protect our forces deployed in Europe and our allies there from Iranian short- and medium-range missiles."
He said the change comes in part because the U.S. has concluded that Iran is less focused on developing the kind of long-range missiles for which the system was originally developed.
"While the Iranian threat has developed, so too has our technology," Morrell said. Details were expected to be announced later Thursday.
CBS News White House correspondent Peter Maer reports that an official told CBS News that "it will become evident that the way forward enhances our homeland defense and protects our forces abroad as well as our European allies."
The official said review was "driven by an updated intelligence assessment of Iran's missile programs and new advances in our missile defense capabilities and technologies."
Obama's top military adviser, chairman of the Joint Chiefs of Staff Adm. Mike Mullen, told The Associated Press on Wednesday that the administration was "very close" to the end of a seven-month review of a missile defense shield proposal, an idea that was promoted by the George W. Bush administration. Mullen would not divulge its results.
Obama faced the dilemma of either setting back the gradual progress toward repairing relations with Russia or disappointing two key NATO allies, the Czech Republic and Poland, that agreed to host components of the planned system.
Morrell said Thursday, "This improvement to the system has nothing to do with Russia and everything to do with Iran."
NATO Secretary-General Anders Fogh Rasmussen called the U.S. decision "a positive step."
And Konstantin Kosachev, head of the foreign affairs committee in the lower house of the Russian parliament, said, "It reflects understanding that any security measure can't be built entirely on the basis of one nation."
Czech government spokesman Roman Prorok said Ellen Tauscher, a U.S. undersecretary of state for arms control and international security, was briefing Czech officials in Prague and Polish officials in Warsaw on Thursday about Obama's decision.
"This would confirm that Central Europe is not in the center of the Obama administration's interest," said Jaroslaw Gowin, lawmaker for Poland's ruling Civic Platform party. "But maybe the U.S. will offer us an alternative."
Piotr Paszkowski, spokesman for Poland's Foreign Ministry, told The Associated Press he would wait for the U.S. announcement before commenting.
Defense Secretary Robert Gates scheduled a news conference Thursday morning with a top military leader, Marine Gen. James Cartwright, who has been a point man on the technical challenge of arraying missiles and interceptors to defend against long-range missiles that an aggressor such as Iran might lob at the U.S. or its allies.
Obama took office undecided about whether to continue to press for the European system and said he would study it. His administration never sounded enthusiastic about the plan, and European allies have been preparing for an announcement that the White House would not complete the shield as designed.
The decision comes as the Obama administration has been seeking closer ties with Moscow and as Russian President Dmitry Medvedev is preparing to visit the United States next week for the U.N. General Assembly and the Group of 20 nations economic summit.
The plan for a European shield was a darling of the Bush administration, which reached deals to install 10 interceptors in Poland and a radar system in the Czech Republic eastern European nations at Russia's doorstep and once under Soviet sway.
Moscow has argued that the system would undermine the nuclear deterrent of its vast arsenal.
Medvedev has praised Obama for reviewing the plans, though the U.S. administration has maintained the Bush administration's argument that the European missile defense plans are aimed at countering a threat from Iran and pose no threat to Russia.
At an Army missile defense conference last month, military officials discussed possible alternatives for European missile defense, including using shorter-range interceptors from other locations closer to Iran.
Cartwright also has discussed ways the United States might join forces with other nations to watch and protect against Iranian missiles. Using multiple sensors, including some in the Persian Gulf region, theoretically could provide at least a partial shield for Eastern Europe without basing a full radar and interceptor system so close to Russia.
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