A screenshot of the challenge in progress from Swiss app called Castl's Youtube page.

The Austrian government Thursday warned internet users to shun an online cow-kissing challenge, calling it a "dangerous nuisance".

A Swiss app called Castl launched the #KuhKussChallenge ("Cow Kiss Challenge") on Wednesday, encouraging users in Switzerland and other German-speaking countries to kiss cows -- "with or without tongues" -- to raise money for charity.

But Austrian Agriculture Minister Elisabeth Koestinger branded the challenge a "dangerous nuisance" in a statement on Thursday.

"Pastures and meadows are not petting zoos -- actions like these could have serious consequences," she added, pointing out that cows could become aggressive when defending their calves.

Balancing the activities of tourists and cattle farmers is a sensitive topic in Austria's mountain regions, with both being key pillars of the region's economy.

In February, a court in the Tyrol region caused uproar after ordering a farmer to pay 490,000 euros ($555,000) in compensation to the widower of a woman who was trampled to death by a herd of his cows in 2014.

The farmer is appealing the verdict and is being supported by Austria's farmers' federation, which has warned of the "end of our mountain pastures" if the verdict is allowed to stand.

The government has tried to prevent such incidents by publishing a "code of conduct" for mountain walkers and hikers, advising them to avoid herds of cows wherever possible.

"Actions like this challenge fly in the face of our efforts to promote co-existence on the pastures. I simply can't understand it," said Koestinger.