Former National Party president Michelle Boag is facing fresh conflict of interest claims after she solicited money and votes for John Banks' mayoral campaign in emails bearing Super City recruitment contractor Momentum's letterhead.

In one email seen by the Herald, Ms Boag, a management, public relations and communications consultant for Momentum, asked the recipient in an email bearing the company's logo to let her know if they wanted to contribute to Mr Banks' campaign.

In another email also bearing Momentum livery and under the heading "John Banks for Mayor", Ms Boag says she wants "a more experienced Mayor for the first Super City which will also help the National Party to another term in central government".

"For me, this is not the time to be experimenting with a relative political novice by giving Len Brown and Labour a crack at it."

The email also endorsed Alex Swney as "our councillor".

Ms Boag supported Mr Swney when he stood against Mr Banks for the mayoralty in 2004.

Ms Boag urges the recipient to send similar messages to others.

In February, Ms Boag said she would no longer be involved in Momentum's contract to recruit about 45 Auckland Super City executives after claims that her links with Mr Banks' mayoral campaign created a conflict of interest.

Momentum, whose directors include former National Government Prime Minister Jenny Shipley, has more recently faced criticism over its work in recruiting Stephen Wilce as New Zealand's top defence scientist after questions emerged over his credentials.

Labour MP and Auckland issues spokesman Phil Twyford said Ms Boag's association of Momentum with Mr Banks' campaign via the emails "stinks to high heaven".

"There seems to be a complete inability to tell when there's a conflict of interest.

"Any reasonable person would ask ... is that the payoff for the Super City contract?"

When asked, Ms Boag initially said she saw no issue with Momentum's branding appearing on the political emails. The emails were personal and sent in her own time.

"You can't associate Momentum with that at all ... That just happens to be my email signature."

Ms Boag also said that as the branding did not appear on messages as they were being written and she was unaware that it was attached when they were received.

Momentum managing director Bede Ashby told the Herald it was inappropriate for the company's branding to appear on the emails, "and I will certainly stop that".

Momentum was an "apolitical" entity and the messages were "a personal thing".

Ms Boag later told the Herald she had discussed the matter with Mr Ashby and they had agreed it was inappropriate for her personal emails to bear Momentum branding.

"We are talking to our IT people about how to disable it."

Asked about the emails, the executive chairman of the Auckland Transition Agency, Mark Ford, said "I'm not going there".

Mr Ford said Momentum won the Super City contract fairly and squarely and had done an excellent job.