New Zealand dairy giant Fonterra has slammed A2 Corporation's lawsuit against it as irresponsible.

A2 has filed a lawsuit against the dairy company asking the court to make it mandatory for Fonterra to place health warnings on any products containing the A1 milk protein, which A2 claims is harmful.

Fonterra CEO Craig Norgate said that the A2 legal action would not affect the company's newly announced strategy for higher returns for its 13,000 farmer-shareholders, reported the Dominion Post.

Fonterra is targeting returns of at least 13-15% for farmers on top of the payment they receive for their milk.

For an earlier just-food story about the A2 lawsuit, click here.