Somalia accused Ethiopia of smuggling weapons on Tuesday amid fears that arms going into the conflict-riven Horn of Africa nation could end up in the hands of Islamist militants.
The neighbours traded barbs a day after an Egyptian warship unloaded heavy weaponry in Somalia's capital Mogadishu, the second shipment since a security pact in August.
Landlocked Ethiopia, which has thousands of troops in Somalia to fight al Qaeda-linked insurgents, has fallen out with the Mogadishu government over its plans to build a port in the breakaway region of Somaliland in exchange for possible recognition of its sovereignty.
The spat has drawn Somalia closer to Egypt, which has quarrelled with Ethiopia for years over Addis Ababa's construction of a vast hydro dam on the Nile River.
Responding, Somalia's Foreign Minister Ahmed Moalim Fiqi told Reuters: "Ethiopia's motivation behind these defamatory statements is its attempt to conceal the illegal smuggling of weapons across the Somali borders, which are falling into the hands of civilians and terrorists."
He gave no evidence for the accusation, but added that Ethiopia was trying to divert attention from violations of Somalia's sovereignty. Last week, Somalia accused Ethiopia of shipping arms to the semi-autonomous state of Puntland.
Somalia has threatened to expel Ethiopia's troops by the end of the year if the port deal was not scrapped.
The U.N. Security Council lifted a more than three-decade arms embargo on Somalia in December.
Rashid Abdi, an analyst with the Sahan Research think-tank, said the potential for weapons landing in the wrong hands, such as al Shabaab militants, was high. "Al Shabaab is a major beneficiary and in 2023 harvested massive quantities of weapons by conducting raids on enemy (bases)," he said.