Zambia tributaries rise in Angola's central highlands. The edge of the Cuando River floodplain (not its main channel) forms Zambia's southwestern border, and via the Chobe River that river contributes very little water to the Zambezi because most is lost by evaporation. Two of the Zambezi's longest and largest tributaries, the Kafue and the Luangwa, flow mainly in Zambia. Their confluences with the Zambezi are on the border with Zimbabwe at Chirundu and Luangwa town respectively. Before its confluence, the Luangwa River forms part of Zambia's border with Mozambique. From Luangwa town, the Zambezi leaves Zambia and flows into Mozambique, and
Zimbabweans in Zambia exported more corn than it imported. Zambia was considered the "easy option" for Zimbabwean farmers as compared to other potential destinations such as Malawi or Nigeria due to the close resemblance between the soil and climate of Zambia and that of Zimbabwe, as well as Zambia's relative stability; however, farmers who relocated to Zambia typically took on heavy debts denominated in Zambian kwacha while selling their produce abroad for U.S. dollars, which put them into difficulties when the kwacha appreciated almost one-third against the dollar in 2006. Zimbabwean leader Robert Mugabe harshly criticised his Zambian counterpart Levy Mwanawasa for taking