President Barack Obama opened his first Moscow summit with confidence on Monday, predicting "extraordinary progress" out of meetings set to test his diplomatic skills on important priorities such as nuclear arsenal reductions and the fight in Afghanistan.

"The United States and Russia have more in common than they have differences," Obama said he sat down in an ornate Kremlin room with Russian President Dmitry' Medvedev. "If we work hard in these next few days ... we can make extraordinary progress that will benefit the people of both countries."

With both men eager to reset damaged relations, Obama's host launched the high-stakes summit with similar good will.

"We'll have a full-fledged discussion of our relations between our two countries, closing some of the pages of the past and opening some

of the pages of the future," Medvedev said, through a translator. "It is my hope that it will be possible to tackle successfully"' a range of problems from the economy to security and energy and the environment.

The first US-Russia summit since the early part of the George W. Bush presidency presents a challenge for Obama, with Russia home to a wary public, a two-headed leadership and lingering hard feelings. What much of the world will watch are signs of Obama s relationship with Russia's two leaders, Medvedev and his mentor, Prime MinisterVladimir Putin.

The foundation set now could affect how much cooperation Obama gets in areas in which the US needs help from Russia chiefly pressuring Iran and North Korea to give up their nuclear weapons ambitions, but also in tackling terrorism, global warming and the economy.

Both sides talked going in of improving ties and of the importance of early results.