A former Team New Zealand director has condemned management of the Kiwi syndicate for attempting to extort America's Cup hosting fees out of the New Zealand tax-payer.

James Farmer QC, who served as a director of Team NZ from 2007 – 2013, believes Team NZ's attempts to get Auckland to pay a hosting fee for the 2021 event in the wake of big money offers from Abu Dhabi or Russia has the appearance of "corporate blackmail".

The Herald on Sunday last month reported Team NZ had received offers of up to $80 million from offshore locations seeking to host the Cup. They are seeking to use this as leverage to get a hosting fee from local and central government authorities.

In a column published on his legal website Farmer wrote it was a bad look for Team NZ, who built their campaign around bringing the Cup "home".

"It would be helpful and in their own interests in retaining public support if they came out in the open right now and said that this is not a possibility," he said.

"The failure to make a public statement to that effect will, even to people who believe that it is inconceivable that Team NZ would do so, look rather like corporate blackmail aimed at the Government: 'Pay us a hosting fee or we will go elsewhere'.

Farmer said it was "inconceivable" that board members such as Sir Stephen Tindall and Bob Field, who have supported Team NZ for many years would be parties to seeing the Cup disappear from New Zealand shores for the sake of a hosting fee.

"Nor do I believe that men who have made their justified reputations on corporate integrity would negotiate with the Government and/or the Council for the allocation of public funds in such a crude fashion.

Farmer cast doubt on whether it was even legal for Team NZ to take the event to Abu Dhabi or Russia given the contractual arrangements already in place with challenger of record Luna Rossa.

The Auckland QC also questioned the cost of the new foiling monohull class proposed by Team NZ, echoing the concerns of America's Cup legend Dennis Conner.

"No one has ever built a 75-foot fully foiling monohull and the sketches that have been released of the proposed boat show what a breath-taking challenge it will be to design and build such a boat and to make it sail," Farmer wrote.

"The technological complexity (and associated costs) of the AC multihulls must surely look simple and modest compared with what is now proposed."

Farmer stood down from the board of Team NZ just a month out from the start of the 34th America's Cup to be involved with an international committee to investigate the safety rules following the death of Artemis sailor Andrew Simpson in a catastrophic training accident in May 2013.