An aide to U.S. President-elect Barack Obama says the future U.S. leader did not give Poland any commitment on a missile defense shield.

President Lech Kaczynski (file photo)

A statement Saturday from Polish President Lech Kaczynski claims Mr. Obama would go ahead with plans to install the system in eastern Europe.

Mr. Obama's aide Denis McDonough confirms the two men spoke by telephone late Friday night, but says the president-elect only supports a missile defense shield when "the technology is proved to be workable."

The outgoing administration of U.S. President George Bush and Warsaw signed an agreement in August that allows the U.S. to deploy 10 defensive missiles in Poland.  The Czech Republic has also agreed to host part of the system.

U.S. officials say the shield is designed to counter a possible attack from "rogue" nations such as Iran.  But Russia sees the shield as a threat and Russian President Dmitri Medvedev said earlier this week he plans to deploy missiles near the Polish border.

French President Nicolas Sarkozy says he is concerned about Russia's plans.

France holds the European Union's rotating presidency.  The EU released a statement Friday saying the Russian move will do nothing to improve security and will curb future dialogue.

U.S. officials say they have tried hard to address Russian concerns, and called Mr. Medvedev's decision "disappointing."

The Bush administration insists the missile defense system does not target Russia.  

Some information for this report was provided by AP and Reuters.