The political landscape in Zambia has been in flux since Mr Lungu’s six-year presidency ended following his defeat in 2021.
The AU praised the outgoing president, Mr Lungu, for demonstrating strong leadership and statesmanship.
Zambia presidential election results on Monday showed that the opposition leader Hakainde Hichilema secured a stunning landslide victory over incumbent Edgar Lungu.
Sixteen presidential candidates participated in this year’s elections.
Mr Lungu has been in power since 2015 and is seeking to extend his rule.
An estimated seven million people registered to vote in this year’s presidential and parliamentary elections.