Six regional farming ministers of the German green party have written an open letter to Chancellor Merkel urging  her to improve the lot of dairy farmers.

The  ministers – from Lower Saxony, Saxony-Anhalt, Hesse, Schleswig-Holstein, Bremen and North Rhine Westfalia – demanded firm action on the milk price crisis.

It is reported that they’re calling for voluntary or compulsory milk production cuts, as well as for the Chancellor to deliver on the €100 million aid package she promised German farmers a number of weeks ago.

In the letter, the ministers invited the Chancellor to a crisis summit on May 30 in Berlin.

The agricultural crisis, in particular the situation in the dairy market, has in the past months worsened dramatically.”

They wrote that milk producer prices for some dairy companies are at historic lows of less than 20c per litre of milk.

“There is a widespread fear,” the ministers wrote, “that cows will disappear from the meadows.”

“Voluntary action by trade partners to reduce amount must be through a bonus milk scheme …a significant amount of reduction will be doomed to failure because it does not solve the imbalance between supply and demand sustainably.”

The letter was signed by Prof. Dr. Claudia Dalbert, Dr. Robert Habeck, Priska Hinz, Dr. Joachim Lohse, Christian Meyer and Johannes Remmel.

“We would like to ask for the full participation of all trade ministers of the countries and the various organizations of the dairy industry and the dairy farmers,” they wrote.

It is understood that Chancellor Merkel has yet to reply to the ministers, who represent six of the 16 regional farming ministers in Germany (there are 16 federal states, or Länder, in the country).

Last year it was revealed that German milk prices were covering less than 70% of costs.

The average production costs in January 2015 in Germany were 45.64c/kg milk, according to the European Milk Board (EMB), which said that only 68% of this is covered by current milk prices.

A price of 31c cannot cover production costs of 46c and an EU crisis instrument is necessary, the EMB said.