BUCHAREST - George Simion, chairman of the Alliance for the Union of Romanians, and Bucharest Mayor Nicusor Dan will advance to the runoff of Romania's presidential election rerun, scheduled for May 18.

The announcement follows real-time preliminary results by Romania's Permanent Electoral Authority from the first round of the presidential elections rerun on Sunday.

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With over 99.53 percent of ballots counted, Simion, 38, maintains a commanding lead with 40.56 percent of the vote.

Dan, who ran as an independent, is in second place with 20.91 percent. Close behind is Crin Antonescu, the candidate of electoral alliance Romania Forward, with 20.32 percent.

Romania's president serves a five-year term, with a maximum of two consecutive terms allowed.

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Under the Romanian Constitution, if no candidate secures an outright majority in the first round, a runoff will be held between the top two contenders in two weeks.

Romania's presidential election held last November was annulled following allegations of irregular campaigning practices and foreign interference.