The French president opened his speech with a few words in Serbian, stunning the crowd of thousands gathered to hear him. He urged them to be "courageous" and to do whatever it takes "to find a compromise" with Kosovo.
"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.
Serbia and its former province still have a bitter relationship two decades after the Kosovo war led to Pristina breaking away and later declaring independence.
Belgrade refuses to recognise Kosovo, still considering it to be Serbia's southern province, despite a majority of European Union countries and the US recognising it as a sovereign nation.
Their relations have further strained after a decision by Pristina to impose 100 percent tariffs on Serbian products after Belgrade blocked its membership bid to join Interpol.
Serbia has said that talks cannot continue until that decision is revoked. Kosovo however insists that it will not lift the tariffs until Belgrade recognises its independence.
"Events in the last few months are worrying us and decisions contrary to agreements should be revoked," Macron told reporters after meeting with Serbian President Aleksandar Vucic.
"It is our responsibility to provide necessary support to reach an agreement," Macron added.
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.
Macron is the first French president to visit Serbia since 2001 after the visit of Jacques Chirac.
A visit planned for last December was canceled after Yellow Vest anti-government protests turned violent in Paris.
In a sign of increased cooperation, Serbia agreed to buy the French light surface-to-air missile system Mistral.
During Monday’s visit, the two sides also signed a letter of intent for construction of a metro in the capital Belgrade.