Egypt’s President Abdel Fattah el-Sisi has said Cairo stands shoulder to shoulder with Somalia and has slammed Ethiopia’s agreement with Somaliland to obtain access to the sea and establish a marine force base.

“Egypt will not allow anyone to threaten Somalia or affect its security,” el-Sisi said, speaking at a news conference with visiting Somali President Hassan Sheikh Mohamud.

“Do not try Egypt, or try to threaten its brothers especially if they ask it to intervene,” he said.

Somaliland, a region strategically located by the Gulf of Aden, broke away from Somalia in 1991 as the country collapsed into a civil conflict. The region has maintained its own government despite a lack of international recognition.

On January 1, in a memorandum, Ethiopia said it would consider recognising Somaliland’s independence in return for the port access. It would lease 20km (12 miles) of coastland around the port of Berbera, on the Gulf of Aden, for 50 years for military and commercial purposes.

Ethiopia’s current main port for maritime exports is in the neighbouring country of Djibouti.

Sheikh Mohamud, the president of Somalia, rejected the deal as a violation of international law and said: “We will not stand idly by and watch our sovereignty being compromised.”

He arrived in Egypt over the weekend to rally support for his government. Besides meeting President el-Sisi, he met with Arab League chief Ahmed Aboul Gheit and Al-Azhar Mosque’s Grand Imam, Sheikh Ahmed al-Tayeb.

“My message to Ethiopia is that … trying to seize a piece of land to control it is something no one will agree to,” el-Sisi said, noting cooperation on development was a better strategy.

On Sunday, Ethiopia rejected criticism from Egypt over the deal, saying it was merely a commercial agreement aimed at securing access to the sea and not an attempt to annex land.

“It isn’t annexation or assumption of sovereignty over the territory of any state,” Redwan Hussien, national security adviser to the prime minister of Ethiopia, said in a post on X.

Relations between Egypt and Ethiopia have been tense for years over a major dam Ethiopia has built on the Blue Nile.

For over a decade — along with Sudan — the countries have been trying to reach a negotiated agreement on the filling and operation of the $4bn Grand Ethiopian Renaissance Dam.

The latest round of talks last month ended without a deal and Cairo and Addis Ababa traded blame for the failure.

Negotiators have said key questions remain about how much water Ethiopia will release downstream if a multiyear drought occurs, and how the countries will resolve any future disputes.