"The five leaders welcomed the efforts by the Ukrainian government to implement the Geneva agreement, including cooperation with the Organisation for Security and Cooperation in Europe (OSCE) and working towards constitutional reform and decentralisation," Xinhua quoted the Downing Street spokesperson as saying in a statement.
It said the leaders agreed to extend "the current targeted sanctions" on Russia.
The leaders accused Russia of not taking efforts to implement Geneva agreement
The leaders "condemned the absence of any efforts on the part of Russia to support the implementation of the Geneva agreement, and the further efforts to destabilise Ukraine and to undermine the 25 May elections".
A new wave of unrest erupted in Ukraine's east in early April, when pro-Russia activists seized government buildings in the cities of Donetsk, Lugansk and Kharkov.
Russia Thursday began military drills near the border with Ukraine in response to Kiev's "anti-terror" operation, which left five pro-Russia protesters dead.
Russian President Vladimir Putin called the operation "a serious crime", warning of "consequences" if Kiev deployed the army against its own people.
Also on Thursday, Russian Foreign Minister Sergei Lavrov said that the US should use its influence to make the Ukrainian authorities fulfill their commitment to the Geneva agreement on Ukraine.