Labour MP Phil Twyford says he should not have used his parliamentary email to endorse candidates in the local body elections and he is sorry.

Mr Twyford, Labour's Auckland Issues spokesman, met Parliamentary Service officials today following an accusation from Act leader Rodney Hide about improper use of parliamentary resources.

Mr Twyford admitted he asked a staff member to send on his behalf an email to about 1000 recipients endorsing Labour-backed candidates in local elections.

"Parliamentary Services have told me that there is a case to answer and that it has been referred to the Speaker's Office. This was a genuine mistake. I am now aware of the rules and I won't be making this mistake again.

"It wasn't my intention to break the rules and I apologise."

The email urged recipients to vote in local body elections and focuses on the Auckland super city race.

"If you are in Auckland, your choice will help determine what kind of super city we end up with. If we elect the right people to the mayoralty, council and boards they will be able to un-do much of the harm Rodney Hide has done over the last eighteen months," he wrote.

"Vote Len Brown for Mayor."

He also lists other council and local board candidates the party supported.

"It's now clear to me that that was a breach of the rules," Mr Twyford told NZPA.

He said the rules were there for good reasons and he would not be drawn on how he felt about Mr Hide raising the complaint. Mr Hide has recently been in the media spotlight after he revealed he knew about David Garrett's identity fraud - he stole a dead toddler's identity to get a passport when he was 26.

"The issue here is I broke the rules... junior MP learns lesson and moves on," Mr Twyford said.

Ironically Mr Twyford highlighted a conflict of interest issue when former National Party president Michelle Boag solicited money and votes for John Banks' mayoral campaign in emails. She works for Momentum which has been hired to recruit for the supercity and used the company's letterhead.

Mr Hide, who is Minister for Local Government, said he made the complaint about Mr Twyford because he wanted to remind MPs that they were prohibited from using resources provided to them as an MP to endorse candidates in local government elections.

"It is vital to maintain local government's democratic independence and to act in accordance with New Zealand's important democratic principles," he said.

"As such, individual MPs should not use their taxpayer provided resources to influence local government elections in any way."

He said he wanted to caution other MPs against "such inappropriate behaviour".