The Zimbabwean parliament has reportedly issued an ultimatum to former president Robert Mugabe after he failed on Monday to attend a parliamentary hearing where he was due to give evidence on corruption in the diamond mining industry.

Lawmakers wanted to question Mugabe, 94, over his 2016 claim that Zimbabwe lost $15 billion in revenue due to corruption and foreign exploitation in the diamond sector.

The nonagenarian, who was ousted from office in November after 37 years in power, also failed to attend the hearing last week without giving reasons.

“We were expecting former president Robert Mugabe to appear before us as a result of a letter that had been written to him,” Temba Mliswa, mines committee chair and an independent member of parliament, told journalists, according to an AFP report.

The state-owned Herald newspaper said on Tuesday that the mines and energy portfolio had since issued an ultimatum to Mugabe.

The report said that Mugabe risked facing contempt of court charges if he snubbed the committee again.