( BBC ) - US Secretary of State Condoleezza Rice is travelling to Russia for talks issues that illustrate a widening divide between Moscow and Washington.
A more assertive Kremlin has expressed strong opposition to US efforts to extend its controversial missile defence shield in Europe.
Washington's backing for Kosovo's independence has also been attacked.
For her part, Condoleezza Rice has criticised democratic setbacks in President Vladimir Putin's Russia.
The US secretary of state will find it hard to defuse growing tensions with Moscow.
President Putin has accused the United States of pursuing policies that have made the world a more dangerous place.
In return Washington has criticised Moscow for concentrating more power in the Kremlin.
The United States believes that President Putin has backtracked on democratic reforms, but at the same time the Bush administration needs the support of Moscow on a range of issues.
Condoleezza Rice will be trying to reassure Russia about its plans to extend the US missile defence shield in eastern Europe.
Russia remains vehemently opposed at having more US military hardware so close to its own backyard.
The US secretary of state will also try to overcome Russia's objections to efforts to help Kosovo on the path towards independence.
Washington also needs Russia's support to keep up the international pressure on Iran's nuclear programme.
While Washington may be anxious about the direction President Putin is taking his country, it cannot afford to alienate the Kremlin.