You can't call your sparkling wine champagne unless you come from the Champagne region of France and, perhaps one day, you won't be able to call your average bottle of suds an honest Kiwi craft beer without passing a similar test.

A leading craft brewer says he wants the big breweries to stop invading his patch and pretending to be something they're not - and would like a "craft" definition and perhaps a "Brand NZ" quality mark to distinguish genuine from fake.

But senior big-brewing insiders said a gathering tomorrow night of craft brewers, led by Josh Scott of Moa, to "discuss what defines a craft beer" was merely a "marketing stunt for Moa" designed to give them media profile and increase their share price.

Scott's forum at an Auckland brew-pub tomorrow may be the start of a challenge to New Zealand's three brewing giants, Lion, DB and Independent Liquor, with Scott saying he hoped it would produce a "united voice" for the 70-odd independent craft brewers to set industry standards - and speak out against "faux-craft" beer.

He said Lion and DB had rejected invites, but Independent, who make Boundary Rd, would be there.

Lion's external relations director Liz Read said: "If we thought it was a legitimate issue for discussion among all of the brewing industry, we would expect to see the Brewers Guild facilitating such a discussion and on that basis would be very happy to participate."

A hospitality source said Moa were "the wolf in sheep's clothing" because they had become big themselves with investors like former 42 Below Vodka boss Geoff Scott and their growth aspirations threatened other craft brewers.

But Scott says the big brewers had used "smoke and mirrors" in creating packaging and even intricate backstories around their craft-style brands to look like the indies. "They are definitely trying to fool people about what they are, and who they are," he said.

Lion's Crafty Beggars range purports to be made by a "rogue society of nine brewers" and recently underlined its home-style branding by launching "beer insurance" where people can claim free pints if they spill one and write in with a claim.

Lion's Danny Phillips said the nine brewers were genuine: "They are real people with 137 years' brewing experience between them . . . it's a fun, tongue-in-cheek campaign not intended to cause offence that a few have taken too seriously." But Scott said: "I would rather people be honest about it and people got a proper education about it, and see real people with a real brand where you can touch and feel the story, instead of a manufactured story from some marketing guy."

Scott said the sauvignon blanc industry had suffered plummeting prices because it set no rules around who can produce a sav - whereas the pinot noir industry spoke with one voice and shared standards. Without similar action, he suggested, Kiwi craft brewing could end up with a dismal reputation.

His suggestions include craft beers being limited to those who use solely New Zealand-grown hops, to producing a definition of what a craft beer is and some sort of authenticity label for export beers."I would like a united voice," said Scott.