The limits of the European Union’s influence were on Monday laid bare when a summit with countries bordering the Mediterranean to the south and east failed to agree a final declaration.

Nevertheless, Tony Blair, British prime minister, and José Luis Rodríguez Zapatero, his Spanish counterpart who co-hosted the summit, insisted progress had been made in deepening ties with the region and continuing the struggle against terrorism.

“I think that this is an area where semantic agreements are less important than shared spirit and determination,” said Mr Blair.

The 35 countries – the EU member states and their Euromed partners Algeria, Egypt, Israel, Jordan, Lebanon, Morocco, the Palestinian Authority, Syria, Tunisia and Turkey – did endorse a previously negotiated five-year work plan on extending “political pluralism”, modernising the southern Mediterranean’s economies and reducing illegal migration.

They also backed a “code of conduct” intended to increase police and judicial co-operation against terrorist groups, but omitted a definition of “terrorism” the EU had worked on for months.

The EU provides the Euromed region with €3bn ($3.5bn, £2.1bn) a year in grants and loans, but none of the Arab heads of state who had been invited attended the meeting in Barcelona, sending prime ministers and foreign ministers instead.

Arab leaders were wary of attending an event that could be seen as cracking down on groups denounced as terrorists in the west but regarded as freedom fighters by many of their own people.

European leaders were relieved at not having to meet Syria’s President Bashar al-Assad, and Lebanon’s President Emile Lahoud, who are the subjects of an international outcry over Syria's alleged involvement in the assassination of Rafiq Hariri, the former Lebanese prime minister.

By contrast, the organisers’ hopes were hit hard by the absence of leaders such as Egypt’s President Hosni Mubarak and Jordan’s King Abdullah, both of whom are struggling with political challenges at home.

President Muammer Gad-affi of Libya spurned an invitation to attend as an observer, despite EU hopes of reaching a deal to release five Bulgarian nurses sentenced to death in Libya for allegedly infecting children with the HIV virus.

Also absent was President Abdulaziz Bouteflika of Algeria, who was undergoing treatment in a Paris clinic. Mahmoud Abbas, president of the Palestinian Authority, and Recep Tayyip Erdogan, Turkish prime minister, attended the event, as did almost all of the EU leaders.

A dispute between Israel and its Arab neighbours foiled last-minute attempts to agree a final declaration for the 35-nation summit. Israel, which will have early elections, wanted the text to emphasise its pull-out from Gaza and objected to a reference to an Arab peace initiative.

Instead, the conclusions of the meeting were summed up by a chairman’s statement by Britain and Spain.

“This is not binding to all parties; it’s a presidency declaration,” said an Israeli official. “What was binding were the documents which were accepted by consensus, the code of conduct and this five-years’ work plan.”