WELLINGTON, March 3 (AFP) - The slimmers organisation Weight Watchers has teamed up with fast-food giant McDonald's in New Zealand -- in a deal that some of their members are finding difficult to stomach.

The dieting company will put their logo on three different McDonald's meals, that each adds up to 6.5 Weight Watchers' points of a maximum per day of between 18 to 40.

People have a greater chance of losing weight and keeping it off when they do not deprive themselves of every indulgence, Weight Watchers' spokesman Chris Stirk told the New Zealand Herald.

He said the McDonald's deal followed similar arrangements with restaurant chains in Britain and America.

Doctor Robyn Toomath, from the Fight the Obesity Epidemic group, said the move was acceptable if it convinced McDonald's customers to pick a less-fatty food option but it was more likely to attract new customers and normalise the regular eating of McDonald's.

Weight Watchers' members appeared divided about the scheme according to comments on their website message board.

"Weight Watchers should be ashamed of doing a deal such as this," wrote Liz, while Jen added: "This is all about money and it disgusts me to see WW have sold out."

However, Cass said that "just because there's a WW option on the menu doesn't mean I'll have to buy from Maccas" and Maureen said: "For those of us that are on the plan and understand the points thing its not such a bad idea."