Intense rains have disrupted operations at Kenya's only port, delaying the delivery of grain, sugar and coal, while a queue of vessels waiting to offload cargo is building up, its operator said on Monday.

The port of Mombasa serves Kenya, which is east Africa's largest economy, as well as neighbouring landlocked nations including Uganda, Rwanda and Burundi, which rely on it for shipments of vital commodities and oil.

Cargo-handling operations at the port of Mombasa have been adversely affected by torrential rains that have continued pounding the coast region in the last 10 days, Kenya Ports Authority (KPA) said in a statement.

The more-than-expected rains have disrupted port operations especially for products that are brought in bulk like sugar, wheat, maize (and) rice.

Delivery of coal, steel, fertiliser and clinker for cement production was also affected, KPA said, adding that nine container ships and 11 general cargo ships were waiting to berth.

The waiting container vessels are scheduled to offload 4,591 TEUs (20-foot equivalent units), while the general cargo ships will discharge a total of 68,703 tons, which include 6,000 tons and 14,999 tons of bagged sugar and sorghum, respectively, KPA said.