However, Bulgaria's Prime Minister, Boyko Borissov, who hosted the summit, told the press that Greece and Macedonia had "essentially clinched a deal" but that "it was their secret that will be shared first at home".
The European Union would not be able to increase its influence in the Balkan region unless there is "coherence or unity" within the bloc, the French president noted.
The EU Commission said in February it adopted a strategy for supporting the EU integration of the countries of the Western Balkans, focusing on the need for fundamental reforms and good neighbourly relations.
Borissov, whose country now holds the rotating Presidency of the Council of the EU, was speaking at a joint news conference on May 17 with European Council President Donald Tusk and European Commission President Jean-Claude Juncker, who both hailed the Sofia Summit as successful.
The bloc faces a dilemma over Albania, Bosnia, Serbia, Montenegro, Macedonia and Kosovo - wanting to offer them enough to keep them out of Moscow's orbit without rushing to let them join before they carry out important reforms.
"Special attention will be given to creating new opportunities for young people, while ensuring that this contributes to the socio-economic development of the Western Balkans", the document says.
Tusk launched a stinging attack on Trump while adding that he was helping Europe in a way because it had "got rid of all illusions" that it can rely on Washington.
In the summit declaration, a draft of which was obtained by AFP, the Europeans outlined the theme of "connectivity" with investments in transport and infrastructure.
Iran, the Middle East peace process and trade tariffs have become the dishes of the day, overshadowing European Union enlargement talks.
"The summit may be a symbolic act, but it can again trigger a little more dynamism", he said. "We don't want that to happen". Borissov said, asking whether it was not better to negotiate, rather than let "other geopolitical players" - an apparent reference to Russian Federation - enhance their already considerable influence in the region.
According to a draft statement seen by RFE/RL, the agreed compromise is that it would be called "the Sofia declaration" but with a statement in brackets, after the 16 points of the declaration, saying that "we note that our Western Balkans partners align themselves with the above points".
But, highlighting how long and hard their road to membership is likely to be, Prime Minister Mariano Rajoy of European Union member Spain stayed away from the talks since Madrid refuses to recognise the independence of Kosovo.