Ethiopia's army chief on Thursday accused World Health Organisation boss Tedros Adhanom Ghebreyesus – the country's highest-profile Tigrayan abroad – of lobbying to send arms and support to leaders in the dissident region.
Gen Birhanu Jula told reporters on Wednesday that the WHO director general had urged unnamed neighbours to “oppose the war and for [the Tigray People’s Liberation Front] to get arms.”
Gen Jula offered no evidence for his claims and there was no immediate response from WHO headquarters.
Ethiopian forces are moving forward and closing in on the capital of Tigray, the government said on Thursday, after fighting for two-weeks against the province's rulers and it's armed wing.
Prime Minister Abiy Ahmed unleashed a military campaign against 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.
A statement from Mr Abiy’s task force for the Tigray conflict added that the government plans to bring back refugees who have fled to Sudan and was sending missions to the northern region to assess humanitarian needs.
The two-week conflict has killed hundreds, sent 30,000 refugees into Sudan and called into question whether Prime Minister Abiy Ahmed, Africa's youngest leader and last year's Nobel Peace Prize winner, can hold his fractured nation together before national elections next year.
Hundreds of foreign aid workers have left Tigray, warning of a spiralling crisis in an area where hundreds of thousands of people relied on food aid even before the fighting.
US President-elect Joe Biden's foreign policy aide on Thursday urged an end to the fighting.
"Deeply concerned about the humanitarian crisis in Ethiopia, reports of targeted ethnic violence, and the risk to regional peace and security," tweeted Antony Blinken, a veteran diplomat and longtime confidant of Mr Biden.
Ethiopia is a major US ally whose soldiers serve in peacekeeping missions in South Sudan and Somalia. Its military and intelligence services are among the most capable in Africa.
"The TPLF and Ethiopian authorities should take urgent steps to end the conflict, enable humanitarian access, and protect civilians," added Mr Blinken, who is expected to play a senior role in the incoming US administration.
The northern Tigray People's Liberation Front (TPLF) effectively ruled Ethiopia for decades as the strongest force in a multi-ethnic coalition, until Mr Abiy took power two years ago.
On the ground, the TPLF leader said his soldiers still held the important town of Axum, though they had lost Shire as federal troops aimed for the state capital Mekelle.
Assertions by all sides have been impossible to verify because internet and phone connections to Tigray have been suspended and the government has restricted access.