Slightly less that 90 MPs were in parliament for the passing of the Bill that requires a two-thirds majority to sail through.

Zanu PF ordered all its MPs to attend Thursday’s session without fail.

The bill was eventually passed.

In a statement Wednesday, Zanu PF chief whip Joram Gumbo said: “All Zanu PF members of the House of Assembly are kindly requested to attend parliament tomorrow Thursday, September 20, at 2pm without fail.

“I kindly request all members who might have made prior appointments to reschedule them to enable them to attend parliament.”

Earlier in the House of Assembly, Justice Minister Patrick Chinamasa said the Bill would be put to vote Thursday.

The opposition Movement for Democratic Change (MDC) lacked the votes to block the amendment package, but party officials said they decided not to put up even a token fight as a gesture of good will because of progress in the South Africa-mediated talks.

Both factions of the MDC have backed the amendment.

Makokoba MP Thokozane Khupe, who is vice president in the MDC faction led by Morgan Tsvangirai, said they backed the proposals “as a confidence building measure”.

“We remain committed to the principle of a new people driven constitution and a transparent and open process. Our friends and constituencies out there must know that we will never betray this principle; however we are alive to the ongoing discussions and the progress that has been made so far,” said Khupe

“History will judge our actions one day, but l am confident that we as MDC will be able to look history in the face and say we were right.”

Some of Mugabe's critics are particularly concerned about a provision in the amendment legislation that would enlarge parliament's upper house, the Senate, from 66 to 84 members and the lower chamber, the House of Assembly, from 150 to 210 seats. They say that could allow Mugabe to put more of his supporters in parliament.

Another provision would allow parliament to nominate a successor for president in the event Mugabe, the only ruler since independence in 1980, died in office or left because of ill health or retirement. Despite that, he is expected to run next year.