President Aleksandar Vucic on Wednesday urged fellow Serbs to look to the future rather than "suffocating in tears of the past," after Bosnian Serb wartime military chief Ratko Mladic received a life sentence for genocide.
"We should start looking to the future, thinking about our children, peace, stability in the region," he said.
There is a need to "revitalise factories, construct buildings instead of suffocating in tears of the past," Vucic said.
The Hague-based UN tribunal ruled Wednesday that Mladic, widely known as the "butcher of Bosnia", will spend the rest of his days behind bars over 10 charges for war crimes and genocide during the country's inter-ethnic war in the 1990s.
Vucic, a former ultranationalist and once a close ally of late Serbian strongman Slobodan Milosevic, has undergone a remarkable political transformation to pro-European liberal pushing his country's bid to join the EU.
However, the Serbian leader voiced regret that the UN court had not sentenced those allegedly responsible for war crimes against ethnic Serbs, despite there being "living witnesses."
"We are capable of accepting our responsibility, but I'm afraid that the others are not. This shows our strength, not our weakness," he said.
Vucic called on Serbs to ensure that "war and its horrors are not repeated."
Meanwhile Biljana Plavsic, a former Bosnian Serb president and the only woman to be convicted by the International Criminal Tribunal for the former Yugoslavia (ICTY), said she was "scandalised" by the Mladic verdict.
Plavsic pleaded guilty to crimes against humanity and was sentenced to 11 years in jail in 2003.
She was found to have played a leading role in a campaign of persecution against Croats and Muslims.
Now aged 87, she was granted release in 2009.
"I'm scandalised by the fact that such an institution ignores justice and truth," she told AFP by phone.
In the Bosnian Serb wartime stronghold of Pale, near Sarajevo, Milan Jolovic, a Bosnian Serb military veteran was also disappointed, though he said he had expected such an outcome.
"It is obvious that this is a project whose goal is to satanise the Serbian people," he told AFP.