Besigye has slammed the results as a fraud and appealed to the international community not to recognise them
President Yoweri Museveni on Sunday dismissing opposition claims of poll rigging and criticism by the international community.
Museveni was declared the winner of the presidential election with 60 percent of the vote on Saturday, far ahead of the 35 percent won by FDC flag bearer Kizza Besigye.
"The opposition are not leaders, they are just demagogues, liars, just talking, talking," the 71-year-old Museveni said from his home in Rwakitura, his first comments since winning.
Besigye has slammed the results as a fraud and appealed to the international community not to recognise them.
"Besigye cannot be allowed to disturb our peace," Museveni said.
"I am very happy with Ugandans, they came out in big numbers and voted," Museveni added, warning against those who wished to cause violence through protests.
"We shall use both soft and hard means to guard the peace in Uganda... by soft means I mean talking to the youth, who these criminal politicians try to use," he said. "But also we can use non-lethal but tough methods, to deal with any trouble makers."
International observers raised concerns over the proceedings, saying that Uganda's electoral commission lacked transparency and accusing the police of heavy-handed treatment of the opposition.
Museveni dismissed the criticism aimed towards the Electoral Commission and Police by European Union observers.
"I don't need lectures from anybody," he said. "Those Europeans are not serious."
Rigging claims 'rubbish'
"Anybody who is trying to challenge the results of this election must not be serious," Museveni added. "If anyone was rigging, why did we not rig in Kampala? Why did we agree to lose where we can rig? That's rubbish."
Several African leaders extended their congratulations to President Museveni following his victory.
Kenyan President Uhuru Kenyatta wished Museveni "every success as he serves his nation for another term", while Burundi's embattled President Pierre Nkurunziza praised the "well-deserved re-election."
President Hassan Sheikh Mohamud of Somalia -- where Ugandan troops are fighting the Al-Qaeda-linked Shabaab -- said it showed "the maturity of practising democracy in a peaceful manner."