Kiev: U.S. Secretary of State John Kerry was due to visit Kiev on Thursday to discuss Ukraine`s reforms and a fragile ceasefire in eastern Ukraine where Russian-backed separatists are fighting government forces.
Kerry was to fly on to Warsaw later for a NATO summit and U.S. officials have denied the visit is aimed at sending a message to Moscow ahead of Friday`s alliance meeting to address the military threat from Russia following its annexation of Ukraine`s Crimea peninsula in 2014.
The Minsk ceasefire agreement has failed to stop all fighting between Ukrainian government troops and the separatists in eastern Ukraine.
Meanwhile Ukraine is grappling with economic crisis and an ambitious Western-backed reform agenda, which has been slowed by a political crisis.
The peace deal was negotiated by Ukraine, Russia, Germany and France in February 2015 and Ukraine and separatists have repeatedly accused the other side of failing to honour commitments made under the agreement.
Ukraine and NATO also accuse Russia of sending troops and weapons to separatist rebels, a charge Russia denies.
"This is an opportunity to talk about ... the road to full implementation of the Minsk agreements and the security situation more broadly in Ukraine," a senior State Department official told reporters.
The United States is the largest provider of security support to Ukraine.
Kerry will meet senior Ukrainian officials including President Petro Poroshenko and new Prime Minister Volodymyr Groysman.
Under the peace agreement, Ukraine has pledged to hold local elections in eastern regions and pass a law granting them greater autonomy.
But Kiev has said it cannot implement these points until all fighting subsides and it has full control of eastern borders with Russia.
"It`s fair to say that quite a bit of progress has been made on the political aspects of Minsk," the U.S. official said, adding, "There`s still work to be done there, but far more needs to be done to reach an agreement on the security side."
"That will involve concrete conversations about disengagement and ceasefire on the line, (Organization of Security and Cooperation in Europe) access throughout the territory, cantonment (storing under monitor) of heavy weapons – we can`t have an election in eastern Ukraine unless those things happen," the official added.
U.S. President Barack Obama, along with leaders and senior officials from France, Britain, Italy and Germany will discuss political and security aspects of the Minsk accords in Warsaw.