Brussels - Nato said on Wednesday there has been no request or discussion about the military alliance helping West African forces to retake control of northern Mali from Islamist guerrillas.
"There has been no request or discussion on a possible role for Nato in Mali," said a Nato official who asked not to be named.
On Tuesday, the head of the African Union, Benin President Thomas Boni Yayi, said "Nato should play a part and the African force would lead the way as was done by Nato in Afghanistan".
The West African state of Mali has been cut in two since early last year when Tuareg rebels seized cities in the arid north and east of the country, sparking fears they could destabilise the whole region.
"Nato is not involved in this crisis but the situation in northern Mali is of course of grave concern to us all. It threatens the security and stability of the country, the region and beyond," the Nato official said.
Nato welcomed last year's UN resolution on Mali and the European Union's decision to plan a planning for a military training operation for Mali armed forces, the official said.
"We are hopeful that the efforts of the international community will help restore the rule of law in Mali," the official added.
Yayi, speaking on a visit to Ottawa with Canadian Prime Minister Stephen Harper, said: "I think that Nato should add its forces to our efforts so this could be an international mission."
Overnight Monday, Malian soldiers fired warning shots at Islamist fighters near the town of Mopti, some 650km northeast of the capital Bamako.
Mopti is the first major town south of the vast swathe of desert which Islamist groups and Tuareg rebels seized after a coup in Bamako last March.
One regional security source said he was "deeply worried" and suspected the Islamists planned to head southwards into government-held territory.