Politicians launched into accusations and counter-accusations after Mr Kohl's top espionage aide, Bernd Schmidbauer, announced last month that a list of agents who had infiltrated former West Germany would be handed over to prosecutors.
'The materials stemming from the activities of East Germany's state security service are being evaluated in a just and legal way,' Mr Kohl said in a statement. 'For me it is self- evident that these documents should not be used for party-political business.'
The agents were identified only by code- names, but were drawn from the ranks of politicians, regional leaders, scientists and journalists. On Sunday, Mr Schmidbauer said there were files on 2,000 West Germans alleged to have spied for the East and its Stasi security service. The files have not been made public, their origin is obscure - and the scope for scoring party points with insinuations of Cold War skullduggery is unlimited.
All last week, the media buzzed with speculation that Karl Wienand, the former parliamentary whip for the opposition Social Democrats (SPD), had spied for East Germany. The Federal Criminal Office admitted it was investigating Mr Wienand, brought him in for questioning - and then said the allegations had not been substantiated.
The SPD says the rumours amount to political character assassination and are being fed by Mr Kohl's chancellery. Many have centred on politicians from the SPD and Mr Kohl's Free Democrat junior coalition partners, who maintained contacts with East Germany at a time when the SPD Chancellor Willy Brandt was promoting East-West detente.
'I would say the leak is the chancellery,' the SPD leader, Rudolf Scharping, told national television news. 'This is not just party-political mud-slinging. There is no respect for citizens' innocence; their reputation and existence are threatened.'
The 2,000 suspects are said to come from all parties, and Mr Kohl's attempt to stop the issue becoming political may reflect fears his own Christian Democrats could be affected.
The secret origin of the files has angered the SPD and Free Democrats. Since the Stasi destroyed foreign intelligence files to stop them falling into Western hands with German unification in 1990, the new dossiers were widely assumed to be copies that the Stasi passed to its Communist overlord, the Soviet KGB.Reuse content