One week ahead of the provincial council elections, which will determine the make up of the upper house of parliament, GroenLinks and Forum voor Democratie are set to make the most gains, according to a new poll of polls.

The 75 seats in the senate are allocated on the basis of a vote by the 500 provincial council members in May. The government needs a majority in the upper house to steer through controversial legislation but all the polls show that it will lose a large number of seats.

The ruling VVD will remain the biggest party in the senate with 12 seats, a drop of one on four years ago. GroenLinks will add five seats to take nine, putting it level with the anti-immigration PVV. Support for Geert Wilders’ party is unchanged on 2015.

New party Forum voor Democratie is set to debut in the senate with eight seats, putting it just ahead of the CDA on seven (down five). Support for the liberal democratic party D66 is likely to halve from 10 to five.

If the poll, an amalgam of two separate opinion polls, is correct, it means the two anti-EU and anti-immigration parties (PVV and FvD) will control 17 of the 75 seats in the senate, giving them an important voice in the remaining years of this coalition period.

In total, 14 parties are likely to win representation.

‘The fragmentation of the political system is continuing,’ said compiler Tom Louwerse. ‘You can assume that the Netherlands will become even more difficult to govern with such a situation in the upper house.’

Only Dutch nationals can vote in the election for the 12 provincial councils which take place next Wednesday.

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