"Those New Zealanders seeking up to $2000 worth of shares will not have their offer scaled back," he said. "In other words, New Zealanders applying for up to $2000 worth of shares are guaranteed to receive the shares they apply for.
"Big institutions aren't getting any guarantees, so this is another way we are putting everyday New Zealanders at the front of the queue," Mr Key added.
The definition of New Zealander for the purposes of the offer will be a New Zealand citizen or permanent resident ( or if it is a company, a declaration that is it majority New Zealand owned), and the person must have a valid IRD number, an New Zealand bank account and a New Zealand address.
The sale is scheduled to be completed by November unless it is delayed by court action.
Mr Key also said that a loyalty bonus of extra shares would be given to New Zealand investors who held on to their shares with details still to be worked through. But it would probably apply after three years.
A syndicate of share brokers and banks has been appointed to help with the marketing and sale of shares by New Zealanders.
People will be able to get a prospectus from over 500 bank branches throughout the country and there will be an 0800 number.
"We will make it as easy as we can for New Zealanders to take art in the share offers," Mr Key said.
The Prime Minister added that the partial share sale was "a win-win" and he stood totally behind the policy.