The UK's representative at the World Health Organization (WHO), Julian Braithwaite, has posted on Twitter a photo of himself with the Ethiopian head of the body, Tedros Adhanom Ghebreyesus.
Ethiopia's army chief has accused Dr Tedros of procuring weapons for the Tigray People's Liberation Front (TPLF), which is fighting federal troops.
Dr Tedros has not yet responded to the BBC's request for his comment on the allegation.
Mr Braithwaite tweeted about a meeting held on Thursday to discuss the coronavirus pandemic: