United Future leader Peter Dunne is facing fresh attacks over his parliamentary status.
Labour and New Zealand First are questioning whether he can retain a party leader's status now that United Future has been de-registered.
Over the past week, the embattled Ohariu MP has been accused of leaking a top-secret report into the Government Communications Security Bureau.
On Friday the Electoral Commission cancelled the party's registration at its request because it wasn't sure that it had 500 paid-up members.
Before Question Time on Wednesday, Labour MP Trevor Mallard asked Parliament's Speaker David Carter to clarify what that means for Mr Dunne's seating in the House.
Mr Carter said that, for the first time, a party that is recognised under standing orders has ceased to be registered under the Electoral Act.
He told MPs on Wednesday that where public funds are involved, there needs to be certainty about the arrangements behind a party that seeks to be recognised for parliamentary purposes.
"The United Future party was recognised at the commencement of this Parliament. Parties are recognised by informing the Speaker of their leadership, office holders and memberships and any changes there to."
The Speaker has written to Peter Dunne about his party's status and said he would make a decision about Mr Dunne's position once he has had a reply.
Mr Dunne said he would be having a teleconference with party officials on Wednesday night to discuss re-registering the party and it would need time to verify and reconcile its membership.