"I think Europeans will continue to be united on that, I don’t know if the Americans will be united on that, but the Europeans will," Mogherini said. "I cannot answer for the United States. I can say I was receiving reassuring messages, but I don’t know if there will be divisions in the United States on this. I hope not."
Mogherini, who is visiting the United States, noted that she met with US lawmakers on this issue and the meetings were positive.
"In particular we agreed that as long as the Minsk agreements are not fully implemented, sanctions would remain in place," she explained.
Mogherini explained that, "For us this is an essential point," and added she believes "in Congress this is an essential point as well."
The EU foreign policy chief also said she discussed with US Secretary of State Rex Tillerson how to better support implementation of Minsk accords.
In 2014, Washington and Brussels imposed a series of sanctions on Russia accusing it of the alleged involvement in the crisis in Eastern Ukraine.
Russia has repeatedly refuted any interfetrence in Ukraine and introduced countermeasures.