Even as officials sorted through this latest disturbance, the State Department sought to build a public case against Russia for the wider unrest. The photo images released Monday show militants brandishing Russian weapons and wearing uniforms similar to those worn by Russian forces. The militants look similar to the forces that moved into Crimea in March, ahead of a referendum there that resulted in the peninsula being annexed by Russia.
Secretary of State John Kerry and Lavrov spoke by telephone Monday but appeared to break little new ground. Russia's foreign ministry said Lavrov told Kerry that the Ukrainian government was unable and unwilling to stop what the Russians call extremists in eastern Ukraine.
Biden planned to meet Tuesday with government leaders who took over after pro-Russia Ukrainian President Viktor Yanukovych was ousted in February following months of protests. He will speak with Arseniy Yatsenyuk and Oleksandr Turchynov, the acting Ukrainian prime minister and president. The vice president is also scheduled to meet with legislators from across the country and democracy activists before returning to Washington Tuesday night.
He held a series of meetings Monday with U.S. Embassy officials, members of Congress also in Kiev for an update on the crisis and the Organization for Security and Co-operation in Europe's chief monitor in Ukraine.
A senior administration official told reporters onboard Air Force Two en route to Kiev that Biden planned to announce new technical support to the Ukrainian government to implement energy and economic reforms. The official, speaking on a condition of anonymity to allow Biden to publicly announce any agreements, said the vice president also will follow up on recent U.S. commitments of non-lethal security assistance and discuss what more Washington can offer to help.
Biden also planned to discuss preparations for next month's Ukrainian presidential election and the latest developments in eastern Ukraine, where insurgents are accusing leaders in Kiev of aiming to suppress the country's Russian speakers in the region.
The Obama administration official told reporters that the assistance Biden will announce includes technical expertise to increase production and boost energy efficiency to reduce reliance on oil imports from Russia. The economic help includes advice to make sure international funding is allocated effectively and that all parts of the country are benefiting.
Julie Pace reported from Washington. AP National Security Writer Lara Jakes in Washington and AP writer Jim Heintz in Moscow contributed to this report.
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