Russian President Dmitry Medvedev says the summit with President Barack Obama is a "first but very important step" toward revitalizing relations between Russia and the United States.
Medvedev says better relations would benefit both countries and also the rest of the world. He spoke Monday at a joint news conference in the Kremlin.
Medvedev appears to be responding to urging from the Obama administration for Russia to move beyond Cold War thinking.
Many in Russia believe the United States is determined to weaken Russia, and are skeptical of U.S. programs touted as benefiting both countries.
Obama is to meet Tuesday with Prime Minister Vladimir Putin, whom he has described as having one foot stuck in a Cold War mentality.
Medvedev says a preliminary deal with the U.S. to reduce stockpiled nuclear weapons is a "reasonable compromise" on the crucial issue. But Medvedev said serious differences remain over the possibility of a U.S. missile shield in Europe.
They struck a preliminary deal to reduce their nations' stockpiles of nuclear warheads to as few as 1,500 each, aiming toward the lowest levels of any U.S.-Russia arms control agreement, and to cut delivery vehicles.
The presidents issued a joint declaration pledging to evaluate ballistic missile threats, but the U.S. did not pledge to refrain from deploying missile-defense facilities in Europe.
Meanwhile, President Obama says he wants to host a summit on global nuclear security next year.
Obama suggested the event at a news conference Monday after his talks with Medvedev. Obama said the spread of nuclear weapons is an urgent issue the United States and Russia must take the lead on.
The U.S. president said it will be very difficult for either country to show leadership unless they are willing to manage and reduce their own nuclear stockpiles in a rational way.