Independent MP Brendan Horan has claimed in Parliament that the New Zealand First Leader's Office Fund has been misused. He has asked Parliamentary Service to investigate and report to the Speaker of the House.
Parliamentary rules prohibit the fund being used to solicit members or money or to ask for votes.
Mr Horan told the House on Wednesday that New Zealand First is using taxpayer-funded computer software for party political purposes, such as campaigning and fundraising.
"New Zealand First paid tens of thousands of dollars out of the Leader's Budget to develop this software and has their parliamentary staff working to run the programme for election year. This is a clear breach of Parliamentary Service guidelines."
But New Zealand First leader Winston Peters later said the accusations are without foundation.
"Well, it would be comical if it wasn't so pathetic and it's baseless in the extreme. The truth is that he didn't say one word of truth in that whole speech he made. The Vanguard system has not even been launched yet."
Mr Peters said the Vanguard programme was purchased out of the Leader's Fund, but denied any allegation of wrongdoing or misuse of the fund, including Mr Horan's claim that parliamentary staff are doing work on behalf of the party. He insisted it would be used within the rules.