Replacing Dmitry Rogozin, who has been appointed a deputy prime minister, Grushko faces a number of challenges, especially the U.S.-led NATO deployment of air defense weapons in Eastern Europe.
"The problem of deploying U.S. anti-missile systems in Eastern Europe will be in a spotlight of Russia and NATO, although the principle decision will not be made in Brussels but in Washington," Vyacheslav Nikonov, deputy head of the State Duma Committee on International Affairs, told reporters.
With an eye on possible further expansion of NATO, he said that should NATO move closer to Georgia's accession, it would result in serious worsening of Russia-NATO relations.
Grushko, 57, has worked in the Russian Foreign Ministry for nearly 35 years. As a deputy foreign minister since 2005, he has been in charge of European security and relations with NATO.