Air New Zealand's stake in Virgin Australia has been diluted following the issue of shares to Singapore Airlines but it is not clear whether this country's carrier will top it up.
As part of a series of deals announced this week, Singapore Airlines took a 10 per cent stake in Virgin following the issue of new shares.
Air New Zealand has 19.99 per cent of the company before the issue of new shares and has the option of buying more shares to retain that stake.
The airline's group general manager Australasia Bruce Parton said: "We've not formed a public view on it yet. Obviously we have the right to."
Air New Zealand built up its shareholding in Virgin Australia last year, partly to gain a presence in the Australian domestic market.