NZ First will not face any sanctions in relation to allegations of misuse of taxpayer funding made by its former MP Brendon Horan.
Mr Horan had claimed in a complaint to Speaker of the House David Carter that Parliamentary Service funding to run NZ First's offices in Parliament had been used for party political purposes including fundraising activities.
Read more: Horan hurls more allegations at Peters
However a spokesman for Mr Carter this morning said an investigation into the claims had been concluded and "no further action will be taken unless further evidence is produced".
"NZ First is disappointed that both it, and Parliamentary Services, have been forced into an extensive, time-wasting exercise because of baseless claims by a disgruntled member of Parliament, Brendan Horan", Leader Winston Peters said this morning.
"NZ First's parliamentary staff have been put through unnecessary scrutiny, because of these claims.
"This has been a disgraceful abuse by an MP of the process around parliamentary funding, and New Zealand First is concerned at the undue media attention and time this MP's abuse of process has been given."
Mr Peters noted that the National Government had given some if its question time in Parliament to Mr Horan to enable him to make "a number of baseless allegations".
"NZ First believes that MP and the Government should now apologise to New Zealand First, the Speaker, and the public for these dirty underhand tactics."
Mr Horan this morning said he was "unapologetic for raising serious concerns" about NZ First's use of parliamentary resources.
Mr Peters' concerns about staff being put under scrutiny were "a bit rich coming from a party leader who sacked two staff members on hearsay, denied one of his own MPs due process, and hid behind parliamentary privilege to smear that MP".
"I stand by my decision to bring this matter to the Speaker's attention. While I accept the Speaker's findings, there are anomalies that are remain unexplained," said Mr Horan said.
Mr Horan's allegations included claims NZ First's "Vanguard" constituency management software was being used for party political purposes but was being operated by parliamentary staffers.
He called on NZ First to explain the recent sudden departure of its Director of Operations, Api Dawson, from the party's Parliamentary office and questioned whether that meant Mr Dawson would now be "free to continue to work on the Vanguard software for party political purposes, and be paid as a consultant from the Leader's Office budget while no longer being subject to the Code of Conduct for Parliamentary Service staff?".
Reacting to this morning's news, the Taxpayers Union said it was "time for the Parliamentary Service to come under the Official Information Act so the public can know what's going on" with regards to NZ First.
"In no other government agency would this level of secrecy be tolerated. We are still none the wiser as to whether taxpayer money was used to fund the Party's Vanguard software, or whether redundancy payments were made to keep disgruntled staff quiet."