“We will protect the interests of the Axel Springer company and the interests of our shareholders and will consider possible legal steps,” company spokesman Edda Fels told news magazine Der Spiegel on Saturday.

Springer took over the private postal service Pin Group in 2007, which filed insolvency after the introduction of a minimum wage for postal workers of €9.80 an hour. The Springer company, which owns the national newspapers Bild and Die Welt, is thought to have lost over €600 million in the takeover.

The Federal Administrative Court declared the introduction of the minimum wage as unlawful on Thursday because of procedural errors. The wage came into force following a contract between the national postal service Deutsche Post and service industry trade union Verdi.

Verdi chairman Frank Bsirske said that the court’s decision did not damage the principle of the minimum wage for postal workers. “The administrative court found fault with the procedure, but did not criticise the minimum wage itself. In fact it reinforced it,” he told the Passauer Neue Presse newspaper.

Labour Minister Ursula von der Leyen has now been called on to revise the law. Bsirske also repeated his demand for a national minimum wage. “In many sectors work still makes you poor,” he said, accusing the German government of ignoring the problem. “It is a policy of cold ignorance,” he said.

Bsirske said that the new economic conditions in Germany meant that a minimum wage of above the previously demanded €7.50 an hour was needed. “Among our western European neighbours, the minimum wage is currently an average of €8.41 an hour. We should be aiming for somwhere between €8.50 and €9,” he said.