"Of the six chapters we have reviewed, we have made a lot of changes because we have discovered that the drafters had ignored what we instructed them to do and 70% of their content was of their own invention," Paul Mangwana, Mugabe's point man on the constitution, said in The Herald newspaper.

The paper has published what it said was a draft of the constitution, which included a two-term limit for president. That would prevent Mugabe from running again, since he has been in power since 1980.

Mangwana said the party also wanted a clause to protect Mugabe's land reforms, which resettled blacks on thousands of white-owned farms a decade ago.

Zimbabwe's three-year-old unity accord requires a new constitution with democratic reforms before the country can hold elections.

Jessie Majome, who represents Morgan Tsvangirai's party on the committee, refuted the claims as "totally incorrect".

"First of all we don't have a draft except for the leaks of confidential work-in-progress by people who are causing unnecessary confusion," Majome said.