“It is the clerk of parliament who will write to him (Mugabe) to come to parliament.”
Mugabe’s name did not appear on the parliament committee meetings scheduled for this week.
The lawmakers plan to question Mugabe over his 2016 claim that the country had lost $15-billion (R188-billion) due to corruption and foreign exploitation in the diamond sector.
The committee has already interviewed former ministers, police and intelligence chiefs to answer on diamond mining operations at the vast Chiadzwa gem fields.
Mugabe ruled Zimbabwe from 1980 until he was ousted last year after the military took over briefly and his once-loyal Zanu PF party turned against him.
Zimbabwe discovered alluvial diamonds in Chiadzwa, in the east of the country, over 10 years ago, and rights groups have accused security forces of using brutal methods to control the scattered deposits.
Rights groups say over 200 people were killed during operations to remove illegal panners from the area.
Amid allegations of massive looting, Zimbabwe allowed several diamond companies to mine the area – most of them as joint ventures between the government and Chinese firms.