Lobby group the National Constitutional Assembly (NCA) has vowed to frustrate any talks on constitutional reform between the ruling ZANU-PF party and the opposition.
It argues that only Zimbabweans - not political parties – have the right to decide on the matter.
NCA chairman Lovemore Madhuku told IRIN he would consider negotiations on constitutional reforms between the two parties an "illegitimate process", even though the opposition Movement for Democratic Change (MDC) had its roots in the NCA and the labour movement.
"Political parties could only discuss the modalities on how to involve the people," he said.
South African President Thabo Mbeki, on a visit to Zimbabwe in December, and the church, have both urged ZANU-PF and the MDC to negotiate a solution to the country's deep political and economic crises.
While the MDC has denied that any talks have so far taken place, it has insisted that the focus of any dialogue should be on constitutional reforms, to ensure future elections are free and fair.
The NCA, an umbrella civic organisation, successfully lobbied in 2000 for the rejection by referendum of a controversial draft constitution by the government-appointed Constitutional Commission.
After that defeat, President Robert Mugabe said the country would stick with its original constitution, which has been much criticised for the power vested in the presidency.
The NCA proposes "people-driven" reforms, based on a national consultative process.
This article was produced by IRIN News while it was part of the United Nations Office for the Coordination of Humanitarian Affairs. Please send queries on copyright or liability to the UN. For more information: https://shop.un.org/rights-permissions