Kagame says the situation has deteriorated as both countries struggle to cope with the economic and social impact of the coronavirus pandemic.
The two nations still face some U.S. proscriptions, complicating attempts to get debt relief that countries on the continent are seeking.
Speaking at a summit of the Organization of African, Caribbean and Pacific States, Kagame urged the nations to “work to harmonize and amplify our voices on the continued need for our countries to have adequate fiscal space to respond effectively.”
China’s foreign minister in January called for the sanctions against Zimbabwe to be lifted, saying they have no basis under international law.
Some officials in Zimbabwe’s ruling party and their related businesses have been under U.S. sanctions since 2001, imposed for allegedly blocking human rights reforms and restricting press freedom under former President Robert Mugabe.
Ties between Khartoum and Washington had been officially strained during the three-decade rule of Omar al-Bashir, but have eased after he was ousted by the army last year following mass protests.
Sudan has announced that the United States has approved Khartoum’s pick of a veteran diplomat as ambassador to Washington, the first such envoy in over two decades.
The appointment came after Sudan’s Prime Minister Abdalla Hamdok visited Washington in December and the two countries agreed to exchange envoys.