"To reach an agreement over names for such a delicate operation often takes time," said Mr Van Rompuy, a former Belgian prime minister. "I was in charge of the formation of a government and I can assure you that it doesn't happen in a day . . . guarantee you can't sort it out in a few meetings."
Diplomats said there was so little consensus that very little debate about specific candidates occurred inside the summit room. Angela Merkel, the German chancellor, said she believed that the foreign policy post should probably go to a member of the EU's group of centre-left Socialists, since the centre-right bloc won the EU's top prize when Jean-Claude Juncker was elected European Commission president on Tuesday.
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But she failed to concede any other post to the Socialists, noting that her centre-right grouping won the most votes in May's European Parliament elections. But French president François Hollande, Europe's leading Socialist, publicly disagreed, saying Mr Van Rompuy's replacement as European Council president should also be a Socialist.
"The president of the commission is from the right," Mr Hollande said. "There should also be on balance a socialist or social democratic component for these positions still to be decided."
The third job to be filled, the head of the eurogroup of eurozone finance ministers, is widely believed to be going to Spain's centre-right finance minister, Luis de Guindos.
Despite the failure to agree any posts, it was a long evening of negotiations with the summit's start pushed back nearly two hours as party groupings consulted over potential candidates.
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Much of the focus was on the frontrunner for the foreign policy job, Italian foreign minister Federica Mogherini, who was publicly opposed by several central and eastern EU countries that believe Rome has been too accommodating to the Kremlin over Ukraine.
At the a pre-summit meeting of centre-right leaders, Ms Merkel pulled aside Donald Tusk, the Polish prime minister, for about 20 minutes and attempted to convince him to accept the European Council presidency in a move to assuage those opponents, according to three EU officials in attendance. But Mr Tusk demurred, the officials said.
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Still, with Ms Merkel's acquiescence that the Socialists should retain the foreign policy post, Ms Mogherini, who was aggressively pushed by Italian prime minister Matteo Renzi, remains the frontrunner. The two other socialists mentioned for the job – Slovakia's Miroslav Lajcak and the Netherlands' Frans Timmermans – may not enjoy the backing of their own governments.
Slovakia has already indicated it will renominate its existing member of the European Commission, Maros Sefcovic, and the Dutch prime minister has said his government was seeking at top economic post and is expected to tap Jeroen Dijsselbloem, the current finance minister and outgoing eurogroup chief, to the commission.
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