Ethiopian federal forces on Monday encircled the Tigray regional capital Mekele, according to a government spokesman.

The development came after Ethiopian Prime Minister Abiy Ahmed issued a 72-hour surrender ultimatum directed at the Tigray People's Liberation Front (TPLF) on Sunday.

"The beginning of the end is within reach," government spokesman Redwan Hussein said, after nearly three weeks of fighting that has destabilized both Ethiopia and the wider Horn of Africa.

The TPLF led an armed struggle in 1991 that toppled Ethiopia's brutal Derg regime. They ruled Ethiopia for nearly three decades until Abiy was appointed in 2018.

Since Abiy's rise to power, Tigrayan leaders have complained of being unfairly targeted in corruption prosecutions, removed from top positions and broadly scapegoated for the country's woes.

The Tigray region has been facing a rebellion since earlier this month. On November 4, security forces loyal to the TPLF attacked the Northern Command of the Ethiopian National Defense Force (ENDF) in Mekele, killing several people.

Read more: Ethiopia: A timeline of the Tigray crisis

Refugees flee conflict zone

Some 40,000 refugees from Ethiopia have traveled to Sudan to escape fighting in the Tigray region. UNHCR spokesperson Babar Baloch said the high rate of refugees is concerning.

"The sheer number of arrivals is really putting all of us under under pressure," Baloch told DW. "The effort now is to get the basic supplies to these refugees who are fleeing."

"It has been a challenge for the non-existing infrastructure in the remote locations in Sudan," Baloch added. "The numbers arriving are just stretching and straining the humanitarian response.

Baloch said that the UNHCR is working with Sudanese authorities to set up a refugee camp further inland.

Tigray leader says people 'ready to die'

The leader of the TPLF denied reports that Ethiopian forces had surrounded Mekele.

"There is no such encirclement so far," TPLF leader Debretsion Gebremichael told news agency Reuters.

Gebremichael also rejected the Ethiopian government's ultimatum to surrender, with the leader telling news agency AFP that his people were "ready to die" defending their homeland.

Clock ticking on ultimatum

Abiy, last year's Nobel Peace Prize winner, on Sunday called on the TPLF to surrender peacefully within three days, saying they were "at a point of no return."

A blackout on communications in the northernmost region of Ethiopia has made claims from both sides difficult to verify.

jsi/rs (Reuters, AFP)