Sweden's Social Democrats won 25.1 percent votes in the European Parliament elections on Sunday, Moderates won 17.6 percent votes, exit polls showed on Sunday.

Exit polls by Valu showed that Social Democrats won 25.1 percent votes, up by 0.9 percent from the 2014 EP elections, and Moderates won 17.6 percent votes, up by 4 percent.

Exit polls also showed that the right-wing Sweden Democrats won 16.9 percent of the vote, up by 7.2 percent from their share of the vote in the 2014 EP elections, and representing the biggest gains of any of Sweden's major parties.

Election booths opened across Sweden at 08:00 Sunday morning. Of the 7.6 million people eligible to vote in Sweden this year, at least 1.48 million voted early - which is an increase of more than ten percent compared to the EP election in 2014.

Preliminary results of the Swedish vote will be reported at 23:00 local time Sunday night.