Dubai Aerospace Enterprise has offered to pay up to NZ$2.6 billion for a controlling stake in New Zealand's Auckland International Airport. The bid was backed by the airport's board on July 23, sending the shares up around 5 percent.

Under the offer, which values the whole of Auckland Airport at NZ$5.6 billion, a new company will be created, in which DAE will have a stake of 51 to 60 percent. DAE was set up last year by the government of Dubai and other interests.

However, a counter-offer could be forthcoming given the high level of interest in Auckland Airport, said Walker Capital Management principal Craig Brown.

"There are other parties sniffing around, and Auckland Airport can get out of this if they get a better deal, so I'm not sure this is the endgame yet," Brown said.

Auckland Airport has been the subject of renewed takeover speculation since May, when Australia's Macquarie Airports was reported to have tried to enlarge its small stake.

The board of Auckland Airport, while backing the DAE deal, said it is not restricted from considering other offers.

Auckland Airport shareholders will be offered NZ$2.34 in cash per share, a share in a new airport company with a convertible loan note attached, and a special dividend of 7 NZ cents per share. The offer gives an equivalent value of NZ$3.80 a share, a 15 percent premium to the stock's closing price on July 20.

Shares in Auckland Airport, one of New Zealand's top 10 companies, gained as much as 5.7 percent after the announcement before settling back to last trade up 3.9 percent at NZ$3.44.

The offer is conditional on 75 percent shareholder approval and will be voted on in November. But the company also warned its full-year profit would be 10 percent lower at between NZ$91 million and NZ$92 million because of higher staff incentive payouts.

The deal also will need approval from New Zealand's Overseas Investment Board.

Auckland Airport said last month it was in talks with investors wanting to buy a stake, after several shareholders rejected a NZ$3.10 a share approach from the Canada Pension Plan Investment Board. The Canadian fund is reportedly still interested, while Spanish roads-to-services group Ferrovial, which owns BAA UK airports business, is also tipped as a suitor.

DAE chief executive Bob Johnson said: "Auckland would be a wonderful beginning to our airports business."

DAE has plans to invest US$15 billion in airport development and airplane leasing and servicing. In April it said it would buy US plane servicing firms Standard Aero Holdings and Piedmont/Hawthorne Holdings for US$1.8 billion.

Auckland Airport handles about 70 percent of New Zealand's international traffic and is midway through a NZ$500 million upgrade to runways and terminals.

The Auckland City Council, which has a 12.8 percent stake in the airport, said it was waiting for more information on the Dubai offer. It has said before it is a long-term shareholder, but last week said it was studying options, including possibly joining a bid.