Members have not reached a deal over how to handle the flow of Europe-bound refugees and migrants, despite a significant drop in arrivals this year, diplomats said.
“As one member reserved their position on the entire conclusions, no conclusions have been agreed at this stage,” the spokesman for European Council President Donald Tusk said in a statement.
Diplomats said the country that was blocking was Italy.
Tusk and European Commission President Jean-Claude Juncker also cancelled a news conference scheduled for Thursday evening.
France and several other EU countries including Italy have reached an agreement on new wording for migration conclusions, a French diplomat said.
The diplomat said among those on board with the draft text were Malta, Spain and the Netherlands, although a Dutch government spokesman later said his country was not part of new proposals that came after Rome blocked an earlier agreement.
“I cannot tell you that everything is settled,” the French diplomat briefed reporters on the summit sidelines.
“But it is significant that we have been able to work with the Italian prime minister and make advances on the idea of ‘controlled centers’ that are backed by greater European support.”
Italian Prime Minister Giuseppe Conte said he would refuse to endorse the conclusions of the meeting in Brussels if fellow leaders fail to do more to help Italy.
“Italy does not need more words, but concrete actions,” Conte told journalists as he arrived at the summit.
“It’s a possibility I hope not to consider, but if we reach that point, on my behalf we will not have shared conclusions,” he added.
Rome has recently refused to allow several migrant rescue boats dock at Italian ports, reviving fresh tensions despite the fact that numbers of arrivals have dipped sharply since the height of Europe’s migration crisis in 2015.
German Chancellor Angela Merkel has described the talks as “make-or-break” for the union.
Merkel told German parliament on Thursday that the fate of the EU rests on its ability to find a solution to deal with refugees and migrants arriving in Europe.
“Europe faces many challenges, but that of migration could become the make-or-break one for the EU,” Merkel said.
“Either we manage it, so others in Africa believe that we are guided by values and believe in multilateralism, not unilateralism, or nobody will believe any longer in the system of values that has made us strong,” she added.
“That’s why it’s so important.”
A June deadline to reach an agreement over asylum seekers has passed, but a solution still remains out of reach.