In Kiev, Clinton will meet new Ukrainian President Viktor Yanukovich, who has quickly consolidated power since taking office on Feb. 25, struck a strategic deal with Russia and declared that Ukrainian NATO membership was off the agenda.
His predecessor had ardently supported the former Soviet republic joining the 28-member Western security alliance, an ambition that unsettled Russia which resents NATO's expansion toward its borders.
She then will attend a meeting of the Community of Democracies in Krakow, an intergovernmental group that promotes democratic norms, and visit Armenia and Azerbaijan, long at odds over Azerbaijan's breakaway Nagorno-Karabakh region.
Skirmishes, sometimes fatal, erupt frequently along front lines near Nagorno-Karabakh, a small mountainous region under the control of ethnic Armenians who fought a six-year separatist war with support from neighboring Armenia.
On Saturday four ethnic Armenian troops and one Azeri soldier were killed in an exchange of fire near the region.
Announcing Clinton's trip, State Department spokesman P.J. Crowley said the United States had "invested a great deal of energy" to try to improve relations and said the visit showed US commitment to try to resolve their disputes.
An estimated 30,000 people were killed and 1 million displaced before a cease-fire in 1994 but a peace accord has never been agreed and the ethnic Armenian leadership's independence claim has not been recognized by any country.
The dispute between mostly Muslim Azerbaijan and mostly Christian Armenia remains a threat to stability in the South Caucasus, an important route for oil and gas supplies from the Caspian region to Europe.
Clinton ends her trip in Georgia in a gesture of support for the former Soviet republic. Critics have accused the Obama administration of improving ties with Russia at the expense of Georgia — a charge US officials deny.
In a five-day war in August 2008, Russia crushed a Georgian assault on South Ossetia launched after days of clashes between Georgian and rebel forces and years of growing tensions between Moscow and US-ally Tbilisi.
"The secretary's trip will be a tangible manifestation of our ongoing commitment to Georgia's territorial integrity," Crowley told reporters.
