Aleksandar Vucic has been sworn in as Serbia’s president, telling his supporters he will work on peace and stability in the Balkans.

Mr Vucic, a former ultra-nationalist turned self-declared pro-European Union reformer, formally resigned on Wednesday from his prime minister’s post after winning the presidential election by a landslide in April.

Addressing thousands of cheering supporters in front of parliament, he said: “I promise I will keep peace and stability, guard and protect the future of our children.”

There were sporadic clashes between his supporters and opponents in central Belgrade as police prevented demonstrators from reaching the parliament building.

The presidency is largely a ceremonial post, but it is widely believed Mr Vucic will continue playing a major role in Serbian politics from behind the scenes.

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