Dakar - A first round of Senegal-Gambia talks to end a three-month border blockade has ended without agreement amid an impasse over a long-delayed bridge project, a senior advisor to Senegal's foreign minister said on Monday."We will consult our experts about the issue of the bridge, and the next meeting will be in July," the advisor said after several hours of talks between Senegal's foreign minister Mankeur Ndiaye and his Gambian counterpart Neneh Mcdouall-Geye on Sunday.The advisor said the Dakar government would encourage militant truckers blocking commercial traffic to halt the standoff. "Senegal will work with those involved to re-open the border to traffic," the source said.The blockade, which has created shortages of essential daily items on both sides of the frontier, followed the Gambia's decision to slap a hundred-fold hike on fees for trucks entering its territory.The Gambia's tiny landmass is completely surrounded by Senegal, and it is reliant on its larger neighbour to import essentials such as fuel. The hike on fees came without warning in February, infuriating Senegalese drivers, and was later reversed.Senegal's militant transport trade unionists have told AFP they will continue their blockade until they win 24-hour passage across the border and clear progress on building a bridge.A bridge spanning Gambia's river would allow much faster journey times between northern and southern Senegal, but an initial plan to complete a bridge by 2017 has been delayed for decades.Mcdouall-Geye has told journalists that the proposed design of the much-delayed bridge was unacceptable in its current form and would hamper navigation."[The river] has to be navigable. The design of the bridge doesn't allow it to be navigable," she said, also invoking concerns among environmentalists that it could damage the delicate ecosystem of the area.