HARARE - Zimbabwe's main opposition said on Wednesday it planned a protest next week to demonstrate against a crumbling economy and press for a new constitution it says will guarantee free and fair elections scheduled for March.

"Our march will be dubbed the freedom walk and is intended to highlight the suffering and plight of Zimbabweans, our demand for a new constitution before the elections and most importantly an even electoral field," Tendai Biti, the secretary general of the Movement for Democratic Change (MDC), told journalists.

Biti said the opposition had notified the police as required by law and would meet law enforcement agents later on Wednesday to discuss the protest march, which has been set for January 23.

Zimbabweans have tended to stay away from demonstrations mainly over fear of a heavy handed state response.

MDC leader Morgan Tsvangirai said earlier this month the party might boycott the elections unless President Robert Mugabe's government implemented a new constitution.

Mugabe's ruling ZANU-PF and the MDC have been in South African-mediated talks on revamping the constitution since June in an effort to end political and economic turmoil in the southern African country, and ensure future election results are accepted by all parties.

The talks are part of a Southern African Development Community (SADC) effort after Tsvangirai and dozens of MDC leaders were reportedly beaten in custody last March after an aborted rally against Mugabe and his government.

The events drew strong international criticism against Mugabe, who turns 84 next month and Zimbabwe's sole leader since independence from Britain in 1980, and heightened calls for him to adopt democratic reforms or step down.

Once southern Africa's bread basket, Zimbabwe now suffers from official inflation of nearly 8,000 percent, frequent food and fuel shortages and unemployment of about 80 percent.

STICKING POINT

The MDC and ZANU-PF have agreed on a new draft constitution but there is a deadlock over when it should be adopted. The MDC wants it implemented before national presidential and parliamentary elections while ZANU-PF wants it after the vote.

In South Africa, Deputy Foreign Affairs Minister Aziz Pahad told reporters it appeared Mugabe and the MDC had agreed on all substantial issues in the talks, but the constitution remained the sticking point.

Biti said the march would test ZANU-PF's commitment to democratic reforms after agreeing at the talks to ease tough security, media and electoral laws. The laws, which were passed by parliament last year, are still to be signed by Mugabe.

"We have to test the sincerity of ZANU-PF but this (march) is without prejudice to the SADC dialogue, which we remain committed to. We are cautiously optimistic that an outcome may come soon," Biti said.

Critics say Mugabe has in the past used state security agents to harshly quell protests against his government but analysts say tension continues to swell among a population ravaged by rising poverty and lately shortages of cash.

"The MDC's biggest challenge is to mobilise despondent Zimbabweans to join the march even if police allow it. People are tired, they have lost hope and are fearful given the regime's past response to demonstrations," said John Makumbe, a political commentator critical of Mugabe's rule.