Since the early 1990s, Estonia has been involved in active trilateral Baltic states co-operation with Latvia and Lithuania, and Nordic-Baltic co-operation with the Nordic countries. The Baltic Council is the joint forum of the interparliamentary Baltic Assembly and the intergovernmental Baltic Council of Ministers. Estonia has built close relationship with the Nordic countries, especially Finland and Sweden, and is a member of Nordic-Baltic Eight ''(NB-8)'' uniting Nordic and Baltic countries. Joint Nordic-Baltic projects include the education programme Nordplus and mobility programmes for business and industry and for public administration. The Nordic Council of Ministers has an office in Tallinn with a subsidiaries in Tartu and Narva. The Baltic states are members of Nordic Investment Bank, European Union's Nordic Battle Group, and in 2011 were invited to co-operate with NORDEFCO in selected activities.