The Committee on European Affairs has been involved in the activities of COSAC since 1997, when Lithuania was still preparing for its EU membership, and has remained an active member of COSAC speaking on the most important items of the EU agenda.

The Committee on European Affairs focuses greatly on cooperation among European Affairs Committees from the Parliaments of the Baltic States and the Sejm and the Senate of the Republic of Poland. Consultations of the European Affairs Committees from the Parliaments of the Baltic States and the Sejm and the Senate of the Republic of Poland that are organised on a rotating basis before COSAC meetings have become traditional since their very first meeting in 2005.