Confirming a move speculated for months, Poland announced plans to host controversial U.S. Patriot missiles and a contingent of U.S. troops that will operate them, by April.

"The Defense Ministry expects the first stage of the stationing of a Patriot battery and a 100-man service team to get under way in the (northern) town of Morag at the turn of April," Poland's PAP news agency reported.

The move comes after a decision by U.S. President Barack Obama last September to scrap a plan by the previous Bush administration aiming to create a defense shield in Europe with interceptor missiles propped in Poland and a radar base in the Czech Republic by 2013.

Although intended to fend off potential threats from rogue states such as Iran, Russia slammed the plan as a serious security threat to its national security.

A revised plan by the current U.S. administration includes the deployment of a new SM-3 anti-missile system in Poland and the neighboring Czech Republic in 2015. But last month Romania announced that it, too, would be the site of 20 missile interceptors and Bulgaria has expressed interest in hosting a base.

This has annoyed Russia, which swiftly threatened to deploy the tactical Iskander missile system in the Black Sea region and beef up its naval base across the border in the Baltics.

The Russian-made Iskander missile system is equipped with two solid-propellant single-stage guided missiles with quasi-ballistic capability, experts say. The missiles have a range of 250 miles, with the ability to carry conventional and nuclear warheads.

Each missile in the launch carrier vehicle can be independently targeted in a matter of seconds, posing a grave threat to U.S. interests in Europe.

Still, "if American technology develops as expected," The Economist weekly magazine reported, "the new shield would cover almost all of NATO's European members against an Iranian attack -- only a small part of Turkey would be exposed by 2018."

That, the report added, marks "a big change from the previous scheme, which was intended mainly to protect America from an intercontinental threat, leaving chunks of Europe unprotected."

Military experts insist that the revised missile interceptors that the United States wants to deploy in former Russian satellite states are hardly a threat to Moscow. They have a shorter range and fly less quickly than the rockets suggested by the previous U.S. administration.

"The main basis for the Kremlin's complaint is political," The Economist reported. "Though Russia grudgingly accepted that ex-communist countries could join NATO, it sees the creation of American bases there as a breach of a promise made when the Soviet Union consented to German reunification."