The death toll in Kenya exceeds that from floods triggered by the El Nino weather phenomenon in late 2023.
More than 7,500 migrants have arrived in England on small boats from France so far this year.
Kenya has historically been a significant exporter of poultry and poultry-related products to Tanzania.
President Mnangagwa, 81, is serving his second and last term after succeeding long time ruler Robert Mugabe following a military coup in 2017.
Kenyan authorities have reported that at least 169 people have died due to flooding, with about 200,000 individuals displaced across the nation.