U.S. Secretary of State Hillary Clinton met with Ukrainian Foreign Minister Kostyantyn Hryshchenko on Tuesday in Washington as part of the third session of the U.S.-Ukraine Strategic Partnership Commission.

"Secretary Clinton and Foreign Minister Gryshchenko underlined both parties' commitment to securing all vulnerable nuclear materials and to increasing cooperation in nuclear security and non-proliferation," the U.S. Department of State said in a statement.

Ukraine, which was briefly left with the world's third largest nuclear arsenal after the breakup of the Soviet Union, agreed to give up the remaining stockpiles of highly enriched material by the next nuclear summit in 2012.

"The Ukrainian party reconfirmed its commitment to get rid of its remaining highly-enriched uranium by the 2012 Nuclear Security Summit. The U.S. party reconfirmed its commitment to provide necessary technical and financial assistance valued at approximately $50 million by the time of the 2012 Nuclear Security Summit as part of this effort, including financial and other resources necessary for the construction of a state of the art neutron source facility that will enhance civil nuclear cooperation," the statement said.

The Nuclear Energy Institute puts Ukraine in its top five countries accounting for the largest percentage of generated nuclear energy. Almost half of the country's energy output comes from NPPs.