The far-right Alternative for Germany (AfD) will seek a court ban on the publication of the decision by the domestic intelligence agency to monitor its activities, a party spokesman told dpa on Wednesday.

The AfD said it was lodging its legal action before an administrative court in Cologne. "The complaint is not aimed at the fact that the intelligence agency is monitoring the AfD, but at the fact that the agency has made this public," the spokesman said. He charged that the publication stigmatized the party, which is represented in all 16 state parliaments and in the federal parliament, the Bundestag.

In January, the domestic intelligence agency, the Verfassungsschutz, said it would step up its observation of the AfD in a clear signal of concern that elements of the party are seeking to undermine Germany's constitutional order. The Verfassungsschutz said it would start treating the AfD as a "Prueffall," or test case, meaning intelligence cannot use undercover agents or other investigative tools in its observations.

A political party may become a test case if the authorities discern initial indications of extremism. According to a report in the Sueddeutsche Zeitung daily, the AfD said there were no legal grounds for the Verfussungsschutz to make its decision public. The party is applying to the courts to impose a fine of up to 10,000 euros for each repetition of its statement.