On 31 March 2021, at the initiative of the Ukrainian side, Minister for Foreign Affairs of Ukraine Dmytro Kuleba spoke by phone with the US Secretary of State Antony Blinken. 

Minister Kuleba informed his counterpart about Russia's systematic aggravation of the security situation at the contact line with the temporarily occupied territories of Donetsk and Luhansk regions and in Crimea as the Russian Federation continues to demonstrate unwillingness to confirm its commitment to the ceasefire. 

Dmytro Kuleba paid special attention to the events at the contact line that took place on 26 March, when Russian occupation forces killed four Ukrainian soldiers. 

Antony Blinken noted that Washington is closely monitoring Russia's actions and gave assurances that the United States will continue to unwaveringly support Ukraine as it defends its sovereignty and territorial integrity. 

They discussed specific areas for strengthening cooperation in the political and security fields.