Vice President Biden spoke this morning with Czech Prime Minister Bohuslav Sobotka.  The Vice President underscored the ironclad commitment of the United States to the collective defense of NATO under Article 5.  The two leaders discussed the situation in eastern Ukraine and agreed that the Ukrainian government had taken significant steps to implement the April 17 Geneva Joint Statement by continuing its outreach to citizens in eastern Ukraine on constitutional reform, proposing an amnesty for those protestors who agreed to lay down their arms and vacate occupied buildings, and working closely with the OSCE to promote dialogue with pro-Russian separatists.  The leaders also took note of the fact that Russia had thus far failed to fulfill any of the commitments it made in Geneva.  The Vice President and the Prime Minister agreed that Russia would face further costs for its destabilizing actions in Ukraine and massing of troops along the Russian-Ukrainian border.  The Vice President also stressed that if Moscow further intervened militarily in Ukraine, the United States and its partners should be prepared to impose sanctions on individuals and entities operating in certain sectors of the Russian economy.