In advance of Pres. Obama's first trip to Russia next week, the White House is serving notice on the Kremlin that he won't be making any concessions to win its approval of a U.S. missile shield in Europe or membership in NATO for Russian neighbors Ukraine and Georgia. "We don't need the Russians," says Michael McFaul, special assistant to the president and senior director for Russian affairs on the National Security Council staff. In a conference call with reporters, McFaul responded with unusually tough talk when asked what reassurances Pres. Obama is prepared to give in his talks starting Monday with his Russian counterpart Dmitry Medvedev.

by Mark Knoller, for CBS News

"We're definitely not going to use the word reassure in the way that we talk about these things," said McFaul. "We're not going to reassure or give or trade anything with the Russians regarding NATO expansion or missile defense." He said Pres. Obama will talk "very frankly" with Medvedev about U.S. national security interests and "see if there are ways we can have Russia cooperate on those things."

Pres. Obama has pledged to reset U.S. relations with Russia, but McFaul said there'd be no concessions on missile defense or NATO "in the name of reset." He said Mr. Obama will make the case that Russia can play a role in enhancing its own security with respect to missile defense.

At the same time, the U.S. and Russian leaders will be discussing new negotiations to further reduce the size of each nation's strategic nuclear arsenals. Under The Moscow Treaty agreed to in 2002 by Presidents George W. Bush and Vladimir Putin, the two countries are committed to reduce the number of nuclear warheads in their arsenals to between 1,700 and 2,200 by the year 2012. "It's too early to talk about whether it's 1,500 or a different number," said McFaul. A new treaty would limit the number of missiles as well as warheads. "That requires a lot of heavy lifting," said McFaul, "and you can't get to the numbers that you're talking about until you know what you can verify."

During his two days in Moscow, Pres. Obama will also meet with Putin, now Russia's prime minister, and also with former Pres. Mikhail Gorbachev. On Tuesday, he'll give what aides call a "major speech" on U.S.-Russia relations and have meetings with a variety of Russian political and business leaders.