French President Emmanuel Macron pledged to relaunch talks to normalise relations between Serbia and Kosovo during an official visit to Belgrade on Monday.
After meeting his Serbian counterpart Aleksandar Vucic, Macron said he would invite delegations from both countries to Paris along with German Chancellor Angela Merkel.
Belgrade's relations with Kosovo — a province that broke away from Serbia and gained its independence in 2008 following a war between Serbian government forces and Kosovar separatists in 1998-99 — have deteriorated since Pristina imposed 100% tariffs on Serbian products after Belgrade blocked its membership bid to join Interpol.
"We are seeing rising tension and sometimes these tensions are fuelled here and there by external powers that have an interest in making sure no deal is found," Macron said.
"Reaching an agreement implies that each party abstains from unilateral and non-constructive gestures and, in that respect, developments over the last few weeks have been a concern, and decisions that were against past commitments must be abrogated."
Vucic asked Macron if he could help Serbia in its bid to join the European Union but the French president made no promises, reiterating that EU decision-making needs to get more efficient before other countries join the bloc.
In a sign of cooperation, Serbia agreed to buy the French light surface-to-air missile Mistral and both sides signed a letter of intent for the construction of a metro in Belgrade.
Belgrade continues to view Kosovo as its own territory despite a majority of European Union countries and the US recognising it as a sovereign nation.
The EU has led talks between the two countries since 2011 which resulted in several technical agreements including the Brussels agreement which aimed to normalise relations and integrate the Serb minority in northern Kosovo.
But in practice, the agreements were vague, and the process was undone after several setbacks.
A series of further setbacks in the last couple of years have seen talks break down, starting with the murder of the ethnic-Serb politician Oliver Ivanović in January 2018. At the end of that year, Kosovo raised customs duties on imports from Serbia to 100% after Belgrade blocked Kosovo's bid to join Interpol. In addition to this, Kosovo decided to upgrade its security force into an army, which Serbia sees as a potential threat that could trigger a military response from Belgrade.
In a joint effort by France and Germany, Kosovar and Serbian presidents, Hashim Thaçi and Aleksandar Vučić, agreed to sit down at the negotiating table in April with another meeting organised for the beginning of July. But the meeting fell through after Pristina declined to remove the 100% tariffs imposed on Serbia last November.