World Health Organization chief Tedros Adhanom Ghebreyesus -- the country's highest-profile Tigrayan abroad, has denied claims that he supports Tigray Peoples Liberation Front (TPLF).
He has, however, called on all parties to work for peace and ensure the safety of Ethiopian civilians.
In a statement on Thursday evening, the WHO boss said: "My heart breaks for my home, Ethiopia, and I call on all parties to work for peace and to ensure the safety of civilians and access for health and humanitarian assistance to those in need."
He added: "I am deeply saddened about reports of casualties and large numbers of people being displaced and seeking refuge in neighbouring countries. In the midst of a global pandemic, I am further concerned about the impact on health."
Ethiopia's army chief on Thursday accused the WHO boss of lobbying in favour of the dissident region and helping them get weapons.
"He has worked in neighbouring countries to condemn the war. He has worked for them to get weapons," army chief Berhanu Jula told a press conference.
He said Tedros had "left no stone unturned" to help the Tigray Peoples Liberation Front (TPLF), the party Prime Minister Abiy Ahmed says he is targeting in a military offensive in the region.
Abiy, last year's Nobel Peace Prize winner, accuses the TPLF, which dominated power for three decades before his appointment in 2018, of seeking to destabilise his government.
"This guy is himself part of that team," said Berhanu of Tedros, who served as health minister in the former government.