The tension between Ethiopia and Egypt appears to have escalated as Cairo extends support to Somalia's peace mission and an offer of security personnel to replace the African Union-backed force, whose mandate is nearing its end.

The prospect of Egyptian troops in close proximity has raised concerns in Ethiopia. Addis Ababa's foreign ministry issued a statement declaring that the country "cannot stand idle while other actors are taking measures to destabilise the region."

Since 2007, Somalia's government has received support from the African Union peacekeeping mission (AMISOM) in its fight against al-Shabab, a group linked to al-Qaida and responsible for deadly attacks in Somalia and neighbouring countries such as Kenya and Uganda.

Last month, Egypt and Somalia signed a security agreement after Somali President Hassan Sheikh Mohamud visited Cairo and held talks with his counterpart Abdel-Fatah el-Sissi.

"We are vigilantly monitoring developments in the region that could threaten our national security," Ethiopia said in a statement.

Tensions between Egypt and Ethiopia have been brewing in recent years, particularly over Ethiopia's construction of a massive dam upstream to generate electricity.

The Grand Ethiopian Renaissance Dam has been a longstanding source of friction among the three nations, with Cairo invoking a decades-old agreement to challenge Addis Ababa's move.

Both Egypt and Sudan have expressed deep concern that the colossal $4.2 billion dam could significantly reduce the flow of Nile water into their territories.

They have consistently called on Addis Ababa to halt the dam's filling until a mutual agreement could be reached, but Addis Ababa has pressed on regardless.

Another point of contention between Egypt and Ethiopia concerns Somalia's breakaway region of Somaliland, which earlier this year entered into an agreement with Addis Ababa to provide access to the Red Sea.

Somalia has sought to block landlocked Ethiopia's efforts to gain access to the sea via a controversial agreement with Somaliland to lease a stretch of its coastline for the establishment of an Ethiopian marine force base.

In return, Ethiopia has agreed to recognise Somaliland as an autonomous country and to give it a stake in Ethiopian Airlines.

Somaliland, which seceded from Somalia over 30 years ago, is not recognised as an independent state by the African Union or the United Nations. Somalia still considers Somaliland part of its territory.