BELGRADE, Serbia—Any partition of Kosovo along ethnic lines is unacceptable, the European Union told Serbia's new leader on Thursday, urging the country to hold talks on normalizing ties with its former province.

Serbia has refused to recognize the 2008 declaration of independence of Kosovo, whose ethnic Albanian majority split from Serbia after a bloody 1998-99 war. Serbia is also seeking to join the 27-nation EU.

But Serbia will only move forward in its bid to join the EU by making "sufficient progress on a key priority: visible and sustainable progress in relations with Kosovo," EU Enlargement Commissioner Stefan Fule said, speaking after talks with Serbia's Prime Minister Ivica Dacic. "Partition of Kosovo is not on the table."

Fule said the EU's goal was to make sure that both Serbia and Kosovo move "on the European integration path without blocking each other."

Dacic, whose nationalist-led government came to power in May, has said previously the best solution for Kosovo would be dividing it into Serb and Albanian parts. Kosovo's Serb-populated north has been a flashpoint because hardline Serbs there do not acknowledge the authority of Kosovo's central government in Pristina.

Dacic said Thursday his government was ready to reopen EU-brokered negotiations with Kosovo.

"It is better for all of us to solve the problems at the negotiating table," Dacic said, but added that "Serbia cannot accept any additional conditions that would mean recognition of Kosovo's independence."

Fule said Serbia must implement other reforms such as stepping up the fight against crime and corruption and furthering respect for human rights, including those of the gay community, whose pride march was banned last week over alleged security concerns from right-wing groups.

"Serbia is expected to pursue its European integration with renewed ambition and perseverance," Fule said.