An impasse in Dutch politics deepened over the weekend after a key lawmaker quit the Christian Democrats, threatening a split in Prime Minister Mark Rutte"s most important possible coalition partner. Rutte"s conservative VVD party finished first in March 17 elections with 21% of the vote, but given the fractured political landscape Rutte needs every member of the centre-right Christian Democrat party and two or possibly three other parties to achieve a majority in parliament. The lawmaker who quit the party, Pieter Omtzigt, said in a statement he intends to retain his seat. Omtzigt has proved something of a nemesis for Rutte. An advocate of transparency, he was instrumental in bringing to light a scandal that prompted Rutte"s previous government to resign. When Rutte began talks to form a coalition after the elections, the process quickly ground to a halt after a document emerged showing Rutte had suggested Omtzigt should receive "a function somewhere else", which was widely interpreted as meaning outside Dutch politics. Rutte initially denied having discussed Omtzigt"s position, then was forced to admit he had. In April Rutte narrowly survived a no-confidence vote over the matter and coalition talks have since been mired over how Dutch politics could become more transparent and whether Rutte can continue. In a snap opinion poll published on Sunday morning by pollster Maurice de Hond, 18% of voters said they would likely vote for Omtzigt if he were to run in new elections.