Mr Mugabe, who was ousted in November after 28 years as president, is being asked to expand on comments he made back in 2016, when he alleged the country had lost $15bn in revenue from diamond mining.

At the time he said it was due to corruption and foreign exploitation.

A parliamentary notice released on Monday said his appearance was "subject to confirmation".

Mr Mugabe, 94, has not been seen in public since November, although a few pictures have been released.

An earlier scheduled hearing was postponed.