Berlin  - A former German interior minister, Otto Schily, was fined Wednesday about 22,000 euros (35,000 dollars), or three months' salary, by the speaker of the German parliament for defying an income-disclosure rule.

Schily, who oversaw German anti-crime forces till 2005, was punished for breaching a parliamentary rule of order that obliges all current deputies to declare their income from non-parliamentary work.

A lawyer whose political career has been built on uncompromising commitment, first as a far leftist, then as a Green and finally as the leader of Germany's fight against terrorism, Schily, 75, claimed that his legal fees for seven clients were confidential.

The speaker, Norbert Lammert, said after the fine was imposed that he had a "lot of understanding" for the deputy's stance and had himself not voted for the rule, but there was no choice but to apply the rule as adopted by parliament.

Schily said earlier he would appeal to an administrative tribunal against the fine, imposed unanimously by the speaker and deputy speakers of the Bundestag lower chamber of parliament.

The penalty, imposed after Schily was given a last chance to comply, was half the maximum fine of six months' salary.

Schily, a Social Democrat who served as interior minister from 1998 to 2005 under former chancellor Gerhard Schroeder, had insisted it was sufficient to tell the speaker his approximate income only. (dpa)