The United Nations will evacuate family members of international staff from war-torn Ethiopia, according to an official document seen by AFP Tuesday, as rebels claim to be advancing closer to the capital.

An internal UN security order asked the organisation to "coordinate the evacuation and ensure that all eligible family members of internationally recruited staff depart from Ethiopia no later than 25 November 2021".

The order came as France became the latest country to advise citizens to leave Ethiopia, following similar advisories by the US and the UK in recent weeks as the fighting between federal forces and Tigrayan rebels edges closer to Addis Ababa.

"All French nationals are formally urged to leave the country without delay," the French embassy in Addis Ababa said in an email sent to French citizens.

Embassy staff were taking steps to facilitate citizens' departure by booking seats on commercial flights and would "if necessary" organise a charter flight, the email said.

Northern Ethiopia has been wracked by conflict since November 2020 when Prime Minister Abiy Ahmed sent troops into the Tigray region to topple its ruling party, the Tigray People's Liberation Front (TPLF).

The 2019 Nobel Peace Prize winner promised a swift victory, but by late June the TPLF had regrouped and retaken most of Tigray including its regional capital Mekele.

Since then the TPLF has pushed into the neighbouring Afar and Amhara regions and this week claimed control of Shewa Robit, just 220 kilometres (135 miles) northeast of Addis Ababa by road.

Some TPLF fighters were believed to have reached Debre Sina, roughly 30 kilometres closer to Addis Ababa, diplomats briefed on the security situation said.

A communications outage in much of the conflict-hit zone has made battlefield movements difficult to verify.

The government has not responded to requests about the status of Shewa Robit.

The African Union's special envoy for the Horn of Africa, Olusegun Obasanjo, is leading a frantic push to broker a ceasefire, but so far there has been little concrete progress.

On Monday Abiy seemed to cast doubt on the prospects of a peaceful solution, announcing he was heading to the front "to lead the defence forces".