BELGRADE – Polling stations opened across Serbia at 7 am local time (0600 GMT) on Sunday in snap parliamentary elections to elect the country's 250-seat National Assembly.

About 6.45 million registered voters are eligible to cast ballots at nearly 8,400 polling stations, including over 90 abroad, according to the country's electoral commission. Polls in Serbia are scheduled to close at 8 pm local time (1900 GMT).

Eighteen electoral lists comprising 2,418 candidates are competing for parliamentary seats.

The competing lists include "Aleksandar Vucic - United Serbia" led by the Serbian Progressive Party, "Student List - Students Win" backed by student groups, and "Ivica Dacic - Stability Factor!" formed by the Socialist Party of Serbia and its allies.

According to the electoral commission, more than 16,000 domestic and foreign observers are monitoring the vote.

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Serbia elects its parliament through proportional representation in a single nationwide constituency, with voters choosing electoral lists rather than individual candidates.

Electoral lists generally need votes equivalent to at least 3 percent of the number of voters who cast ballots to qualify for seat allocation. At least 126 seats are needed for a parliamentary majority.

Under Serbia's election law, election results must be published within 96 hours.

The newly elected National Assembly must hold its first sitting within 30 days. If it fails to elect a government within 90 days, the assembly must be dissolved and new parliamentary elections called.