Daura, who is a close confidant of Buhari was reportedly flown abroad for medical care last week.
He was alleged to have renal problems.
Reacting in a tweet on Saturday, Bashir said there was no iota of truth in the report as Daura is hale and hearty.
Alongside a video of Daura, Bashir wrote, “No iota of truth in the earlier story that Mallam Mamman Daura was flown to London for an emergency medical attention.
“He is hale and hearty. Nigerians should disregard that story.”