Former housing minister Mona Keijzer has decided to leave the pro-countryside BBB after she was passed over for the party leadership following Caroline van der Plas’ decision to stand down.

Keijzer won 100,000 preference votes in the October general election but was rejected as leader in favour of co-founder Henk Vermeer.

Keijzer told the Telegraaf on Monday that she had opted to go it alone and would not join one of the other right-wing parties in parliament. “I’m not going to immediately join another experiment,” she said.

Her decision to leave is the second split since the new selection of 150 MPs were sworn in last year. Earlier, seven MPs for the far right PVV left and set up their own grouping.

Keijzer told the paper she had been promised the leadership when Van der Plas took a step back, and described being bypassed as a “serious breach of faith”.

Keijzer previously left the CDA after twice losing the leadership competition.