The World Bank has offered $200 million in loans to promote economic integration in the Western Balkans as leaders of the region vowed to deepen ties and work together toward joining the European Union.

The announcements from the World Bank and Western Balkan leaders came at a high-level conference on December 7 in Sofia at which the leaders said they had agreed on steps toward deeper integration through improving infrastructure and connectivity within the region and with the EU.

"It is only up to us to demonstrate that the countries of our region bring prosperity rather than problems to the EU," Bulgarian Prime Minister Boyko Borisov said.

Leaders attending the conference included the prime ministers of Bulgaria, Serbia, Macedonia, and Albania, as well as the presidents of Kosovo and Montenegro, and Bosnia-Herzegovina's foreign trade minister.

All of those countries were also slated to be involved in the World Bank's economic integration project.

"We are ready to fund a trade and transport project to help the countries of the region remove the obstacles that exist today," the bank's chief executive, Kristalina Georgieva, told the conference.

"We estimate the benefits to be in the order of $1 billion per year – an important contribution to regional efforts to boost growth and create jobs and opportunities for more people," Georgieva said.

The World Bank's plan aims to streamline border crossings in the region, improve the efficiency of logistics services, and deploy modern technologies to improve freight and passenger transport and get goods to customers faster.

Borisov said the Balkan countries will also seek financial support from the European Bank for Reconstruction and Development and European Investment Bank for their common projects.

He said Bulgaria, which will take over the six-month rotating presidency of the EU in January, will push for more infrastructure, energy, and other projects to help bring aspiring EU members in the Western Balkans closer to the bloc.

The region is still recovering from the wars that tore apart the former Yugoslavia in the 1990s. But Serbia and Montenegro have already started EU accession talks and could join the bloc around 2025, EU officials have said.

Albania has to advance with judicial reforms before it can join the EU, while Macedonia has to resolve a long-running dispute with Greece over its name, which it shares with a northern Greek province.

Bosnia and Kosovo have not as yet carried out reforms required to secure the status of official candidates for EU membership.

Kosovo's President Hashim Thaci told the conference that all Western Balkan countries "must enter the EU in a bloc to ensure long-term peace and cooperation."

With reporting by AP and Reuters