Although Mr D'haeseleer's list gained the greatest number of votes (26.5%) no other party was prepared to work with him as he is a member of the far-right Vlaams Belang.
After two weeks of negotiations, the liberals, greens, socialists and Christian democrats reached agreement on a coalition for the town that is around 25km west of Brussels.
However, the Flemish nationalists lodged a complaint with the Flemish Electoral Commission about what they believed to be illegal campaign tactics on the part of Mr D'haeseleer.
The complaint has been upheld and can only be overturned by the Council of State. The liberals have already said that they intend to take the case to the Council of State.