BBB MP Lilian Helder has unexpectedly quit her seat in parliament during a justice committee debate, citing “irreconcilable differences of opinion”.

Helder, 51, surprised colleagues when she said during the hearing that it was “almost certainly my last debate”. “I will leave as soon as it is clear who will take over the seat,” she said.

She initially declined to go into detail about her reasons for leaving. “Things weren’t always better in the past, but the debates about legislation were more substantial, just like [at this hearing] today,” she told the committee.

After the debate she said she was leaving because of poor working relations with the six other MPs for the farmers’ party. She claimed she had not been involved in the coalition negotiations and never signed the framework agreement that was drawn up by the four parties last July, which set out its plans for government.

“Relations are bad. I don’t feel part of the parliamentary party,” she said.

Helder was first elected to parliament in 2010 for Geert Wilders’s PVV party, but switched to the BBB in September 2023, during the last general election campaign. She said at the time she was leaving the PVV because of “personal and content-related” differences with the party.

Sick leave

BBB leader Caroline van der Plas said she had not been told in advance of Helder’s decision to leave and was unaware of the reason why. However, she said Helder had been on sick leave since she left a party function on December 19.

“On December 19, the last parliamentary sitting day before the Christmas recess, Lilian went home suffering from physical symptoms and reported sick to me.

“Since then she has not been present at the parliamentary party office. Last week she said she was making good progress but still needed to take last week and this week off. I wished her a good recovery.”

Helder disputed comments made by Van der Plas and deputy BBB leader Henk Vermeer when asked about Helder’s absence last week. They told AD.nl the MP was “just ill”, but Helder said: “Whoever is saying that is not being straight. I’m not sick, I’m working at home.”

Vermeer denied that Helder had been left out of the coalition talks. “We put the framework agreement to the parliamentary party and everyone was able to give their opinion,” he said.

Van der Plas would not disclose what prompted Helder to leave the party function on December 19. “Those are private matters and I do not think it is my place to share them with the outside world,” she said.

Helder’s seat will be offered to Martin Oostenbrink, a 36-year-old civil servant from Dedemsvaart in Overijssel.