Ethiopian Airlines, the largest carrier in Africa, on Sunday denied it was transporting weapons and soldiers to the war-torn Tigray region.
Calls to boycott the state-owned airline appeared on social media over allegations it was involved in the nine-month-old conflict.
"Ethiopian Airlines strongly refutes all the recent baseless and unfounded allegations that are running on social media regarding the airline's involvement in transporting war armament and soldiers to the Tigray region," it said in a statement on Twitter.
The war, pitting government forces and their allies against Tigray rebels, has cost thousands of lives and pushed hundreds of thousands into famine, with claims of rights abuses on both sides.
The allegations about the national carrier appeared in numerous Twitter posts, some accompanied by pictures of soldiers boarding one of its planes.
But Ethiopian Airlines said the reports "used various photoshopped, old and unrelated pictures to tarnish our brand".
Flights to and from Tigray, the northernmost region of Ethiopia, were suspended after the conflict erupted in November and after being reopened for a period, the airspace was shut again a month ago.
"We have had no flight to the region since then, and none of our aircraft landed in the conflict area," Ethiopian Airlines said.
The United Nations and other aid agencies have issued urgent appeals for the opening of air and road routes into Tigray, where the UN says more than five million people are in desperate need of help.
The UN's humanitarian chief Martin Griffiths and US aid head Samantha Power are both visiting Ethiopia to press for access to the region.
The Ethiopian government and Tigray rebels have accused each other of being to blame for the difficulties in reaching Tigray by road.