The initial tone of the meeting at the Bush family vacation home on the Maine coast was outwardly very friendly. But when the two leaders get down to business Monday, sharp disagreements are expected.

Russia has not stopped its criticism of US efforts to station a missile defense system in eastern Europe, even though the US government insists the system is intended to protect Europe against "rogue states" such as Iran and is not meant to threaten Russia.

Missile defense and Kosovo question

"If the US is deploying radar in the Czech Republic, this radar will be aimed against us, because there won't be any other targets," Kremlin spokesman Dmitry Peskov said Friday.

Peskov dismissed suggestions the two countries are heading toward a new Cold War, calling it an invention of the media.

Russia is also opposed to having Serbia's breakaway province Kosovo become independent. The United States agrees with a United Nations proposal to allow Kosovo to remain separate from Serbia, but under international supervision.

UN Secretary General Ban Ki-moon said Russia's support is crucial to the plan. Russia has threatened to veto the decision.

"I hope sincerely that this summit meeting…between President Putin and President Bush will find a good solution to this issue," Ban said Monday.

Friendly dialogue?

While neither side expected formal agreements to come out of the meeting, both leaders seemed determined to put on a friendly face. Bush and Putin have been taking speedboat rides and eating lobster at the Bush family retreat in Kennebunkport, Maine.

"I hope that the dialog with this person with whom I've formed good, I would say friendly relations, will take place in exactly that spirit," Putin reportedly said before he left Moscow. "Otherwise, I wouldn't be going and wouldn't have received the invitation."

Putin was stopping in Kennebunkport on his way to Guatemala, where Olympic officials are deciding what city will host the 2014 winter games.