The US has warned Eritrea that it will face sanctions if it does not withdraw its backing for insurgents fighting the fragile UN-backed Somali government.
US envoy to the UN Susan Rice told a Congress committee that Eritrea’s actions would not be tolerated.
In April the African Union, another backer of the Somali government, also called for sanctions over the issue.
But Eritrean officials have repeatedly denied the allegations, calling them a “fabrication” of US intelligence.
The country suspended its membership of the AU in protest at the sanctions call in April.
Ms Rice said the nation was running out of time to avoid strict measures from the Security Council.
“There is a very short window for Eritrea to signal through its actions that it wishes a better relationship with the United States and indeed the wider international community,” she said.
“If we do not see signs of that signal in short order, I can assure you that we will be taking appropriate steps with partners in Africa and the Security Council.”
US Secretary of State Hilary Clinton is due to visit the region next week, when she is expected to meet Somalia’s President Sheikh Sharif Sheikh Ahmed in neighbouring Kenya.
The UN has frequently expressed concern about the flow of arms into Somalia, where hard-line Islamists of al-Shabab and Hisbul-Islam are battling with government forces for control of the capital Mogadishu.
Somalia has been subject to a UN arms embargo for many years but weapons are still freely available in the Mogadishu weapons market.
President Ahmed, a moderate Islamist, was elected by a unity government in January as part of a UN-backed peace initiative.
However, radical Islamists have since gained ground and control much of the south.
Somalia has been mired in civil war for 18 years.
SOURCED FROM BBC