WHO chief Tedros Adhanom Ghebreyesus, the world's highest-profile Tigrayan, on Thursday denied accusations by Ethiopia's army chief that he was lobbying for and seeking to arm leaders in the conflict-torn dissident region.

Prime Minister Abiy Ahmed unleashed a military campaign in the northern region on November 4 with the declared aim of unseating its ruling party, the Tigray People's Liberation Front (TPLF), which he accuses of defying his government and seeking to destabilise it.

Army chief Berhanu Jula told a press conference that Tedros, who served as health minister under TPLF leader Meles Zenawi, was "a part of that team", referring to the party.

WHO head Tedros Adhanom Ghebreyesus, pictured, has been accused by Ethiopia's army chief of trying to get weapons for the dissident Tigray region
WHO head Tedros Adhanom Ghebreyesus, pictured, has been accused by Ethiopia's army chief of trying to get weapons for the dissident Tigray region AFP / Fabrice COFFRINI

"He has worked in neighbouring countries to condemn the war. He has worked for them to get weapons," said Berhanu, without offering evidence to support the claims.

He added that Tedros had "left no stone unturned" to help the TPLF.

Redwan Hussein, spokesman for an Ethiopian crisis committee handling the conflict, admitted "the government is not happy" with Tedros.

"The government is aware that he has been hustling and bustling, calling leaders and... institutions and asking them to... compel the government to sit and negotiate," he told a press conference.

Ethiopia's Tigray region
Ethiopia's Tigray region AFP / Nioucha ZAKAVATI

Tedros said that he saw the destructive nature of war as a child, and has "used that first-hand experience to always work for peace".

"There have been reports suggesting I am taking sides in this situation. This is not true," Tedros, 55, wrote on Twitter.

"I want to say that I am on only one side and that is the side of peace."

Tens of thousands of Ethiopians have fled into Sudan, where they are being housed at a refugee camp built for victims of Ethiopia's 1983-5 famine
Tens of thousands of Ethiopians have fled into Sudan, where they are being housed at a refugee camp built for victims of Ethiopia's 1983-5 famine AFP / Ebrahim HAMID

UN spokesman Stephane Dujarric said Secretary-General Antonio Guterres gave his support to the WHO chief.

"We have all seen the work that he has been doing leading WHO," he said, calling Tedros "an exemplary international civil servant".

Tedros was appointed as the first African head of the WHO in 2017 and has become a household name as he grapples with the Covid-19 pandemic. He has been ranked as one of Time magazine's most influential people.

Abiy's government insists its target is the "reactionary and rogue" members of the TPLF and not average civilians in Tigray.

Prime Minister Abiy Ahmed, right, standing next to President Sahle-Work Zewde at ceremonies in Addis on Tuesday in honour of the armed forces
Prime Minister Abiy Ahmed, right, standing next to President Sahle-Work Zewde at ceremonies in Addis on Tuesday in honour of the armed forces AFP / EDUARDO SOTERAS

But observers have voiced concern about Tigrayans losing their jobs or being arrested for their ethnicity.

Ethiopia's Tigray region
Ethiopia's Tigray region AFP / Nioucha ZAKAVATI

The TPLF led the overthrow of Mengistu Hailemariam, head of Ethiopia's military Derg regime, in 1991 and dominated politics for three decades until the arrival of Abiy who was appointed in 2018.

The party has complained about being sidelined under Abiy, and scapegoated for the country's woes. The bitter feud with the central government this year led the TPLF to hold their own elections in defiance of a postponement due to the pandemic.

On November 4, Abiy said the TPLF had attacked two federal military camps in the region, crossing a "red line".

His controversial campaign has seen warplanes bombing Tigray and heavy fighting, while Amnesty International has documented a gruesome massacre.

A communications blackout in Tigray has made claims difficult to verify, but the overall death toll is believed to be in the hundreds.

Abiy this week insisted the military operation was in its final phase.

Redwan said that "our defence forces are moving forward and closing in on Mekele," the regional capital.

He added that the northern town of Shire, where heavy fighting has been reported in recent days, was already in government hands.

A senior Tigrayan official, Wondimu Asamnew, said that Tigrayan forces "have adopted a defensive posture on all fronts".

A statement from Tigray president Debretsion Gebremichael on Thursday said the army had "called upon assistance from an outside force, with drones starting to be used in the battle."

Meanwhile the UN says a "full-scale humanitarian crisis" is unfolding, with 36,000 people having streamed into neighbouring Sudan, according to that country's refugee commission.

Redwan said that the government was planning to "convince and bring back our compatriots from Sudan and preparations are underway here."

Since the start of fighting, hundreds of people have been arrested for allegedly conspiring with the TPLF, while 34 businesses had their bank accounts suspended for alleged links to the TPLF.

The federal police late Wednesday announced arrest warrants for 76 army officers, some retired, accused of conspiring with the TPLF and "committing treason".

"We continue to receive credible reports of job suspensions of Tigrayan residents elsewhere in the country as fighting escalates in Tigray," Laetitia Bader of Human Rights Watch told AFP last week.