"The head of the office of the head of state added that the United States could play a more active role in promoting peace talks to end the war in Donbass," the press service of the President of Ukraine said in a statement.
Yermak also said that in recent weeks in the Donbass there has been a "dangerous trend" towards an increase in the number of ceasefire violations and an increase in the death toll.
In turn, Sullivan said that the United States will help Ukraine achieve political, economic and security goals.
Also, Washington intends to help Ukraine in gaining NATO membership.
Earlier, the press secretary of the Russian President Dmitry Peskov commented on the situation on the contact line in Donbass.
According to him, provocative actions lead to tragedies.