"I believe it became clear that certain information arriving in the United States did not correspond to the actual situation in the Belgrade-Pristina relations and the level or progress made in the dialogue was not assessed correctly," Nikolic told Tanjug news agency.
Nikolic said Biden told him the United States feels obligated to help resolve the situation because it has recognized Kosovo's independence.
The meeting between Biden and Nikolic was the first in four years between a Serbian president and a U.S. vice president.
It took place in Rome late Monday where both men were there to attend Tuesday's inauguration of Pope Francis as the new head of the Roman Catholic Church.
Nikolic called the talks exceptionally useful.
He said in the future the United States and Serbia would maintain more frequent high-level contact.
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