1973 agreement between the Stasi and the KGB outlining their cooperative efforts to fight "ideological subversion" and uncover "the hostile plans of the enemy." Both secret services would also exchange information gathered by their espionage activities and provide mutual support in infiltrating agents. Of particular mutual interest was espionage against the Federal Republic of Germany and West Berlin. To this end, the KGB was permitted to recruit East German citizens, and the MfS would secure their ongoing contacts.