Aleksander Szczyglo said the decision will be made after a National Security Council session.
Washington announced in January that it would build a radar installation in the Czech Republic and a missile interceptor base in Poland in the next five years to counter possible attacks from Iran or North Korea.
Moscow has strongly opposed the U.S. plans, saying the missile shield threatened Russia's national security and pledged to take adequate measures to counter the U.S. move.
Both Poland and the Czech Republic, which are former Central European Soviet allies and now members of the European Union and NATO, reaffirmed in February their willingness to allow the U.S. to place elements of its missile shield on their territories.
Polish Prime Minister Jaroslaw Kaczynski said in late February that the deployment of U.S. missile elements would guarantee that his country would not fall under Russia's influence at least in the next decades.
Earlier this month, the U.S. State Department said Ukraine was one of the countries with which Washington was cooperating on the missile shield, but people in the former Soviet nation, particularly in the pro-Russian east of the country, have opposed any participation.