Eritrea and Ethiopia were both embargoed. The war did not choose one customer.

During the Ethiopia-Eritrea war, the United Nations did not stop one named shipment. It closed the ordinary route for new foreign military supply.

On 17 May 2000, the Security Council unanimously adopted Resolution 1298. The resolution condemned continuing fighting between Eritrea and Ethiopia and decided that all states must prevent the sale or supply to both countries of arms and related materiel of all types. The measure covered weapons and ammunition, military vehicles and equipment, paramilitary equipment and spare parts. It also covered technical assistance and training related to providing, manufacturing, maintaining or using those items.

The restriction was mandatory and was imposed for 12 months. The UN record says the Council would decide at the end of that period whether to extend the measures, depending on whether the two governments had complied with the demand to stop fighting and resume peace talks. The measures could also end earlier if the Secretary-General reported a peaceful definitive settlement.

SIPRI records the Eritrea entry as entering into force on 17 May 2000 and being lifted on 15 May 2001. The date is close to, but not identical with, the one-year term described in the resolution. That difference should be preserved rather than smoothed away. The resolution established a 12-month framework; SIPRI records the later lifting date.

The embargo covered both sides of the war. It was not a unilateral finding that Eritrea alone was responsible for the conflict, and it did not target only one supplier. The mechanism was a multilateral decision applying to new foreign supply from states and their nationals, or from their territories and flag vessels or aircraft.

There was a narrow exception. The measures did not apply to non-lethal military equipment intended solely for humanitarian use, if the Security Council committee approved it in advance. That exception did not reopen the normal market for weapons, ammunition, military vehicles, spare parts or military training. It allowed a defined humanitarian channel under international supervision.

The timing gave the decision practical importance. The embargo was adopted while the two states were still fighting, after the Council condemned continued hostilities and demanded an immediate cessation of military action. A restriction imposed during a live war can affect replenishment, repairs and acquisition. But the legal fact of the restriction is not the same as proof that a particular front ran short of ammunition or that a military operation failed.