Southern African Development Community (SADC) members have been urged to address the problem of multiple membership to regional groupings.
The call comes from Botswana president Festus Mogae, who said multiple membership will breed problems in the future.
He said member states should choose which regional grouping to belong to before the SADC customs union is effected in 2010.
President Mogae said it is not possible for a country to belong to two customs unions.
He was speaking when he addressed the just ended 27th SADC Heads of State and government summit.
The Botswana leader, who leaves office next year, also said SADC member states need to re-double their efforts to implement regional integration to achieve the Millenium Development Goals.
Mogae said it is sad that member states have been slow to implement commitments that have been signed.
And South African President Thabo Mbeki who assumes the chairmanship of SADC next year said he is confident President Mwanawasa will live up to expectations of the regional grouping as he takes over the chairmanship.
Mbeki said President Mwanawasa will commit himself to the SADC agenda. He also commended Democratic Republic of Congo (DRC) President Joseph Kabila for bringing democracy in the Central African nation.
Mbeki said despite being young, President Kabila has led the people of DRC well.