Nov. 10 (Bloomberg) -- Efforts to implement a power-sharing agreement in Zimbabwe unraveled today as the main opposition rejected regional mediators' proposals to share control of the police force with the ruling party.

At a summit in Johannesburg yesterday, the 15-nation Southern African Development Community said the Home Affairs Ministry should be jointly overseen by two ministers nominated by President Robert Mugabe and opposition leader Morgan Tsvangirai.

``We will not be part of an arrangement that we disagree with,'' Tsvangirai told reporters today after 14 hours of talks ended. ``We disagree with the recommendation of SADC. A great opportunity has been missed by SADC to bring an end to the Zimbabwean crisis.''

Mugabe signed an accord on Sept. 15 with Tsvangirai, leader of the Movement for Democratic Change, to form a unity government following a disputed election. The agreement, which allowed Mugabe to retain the presidency and Tsvangirai to become prime minister, didn't specify who would fill other key posts. SADC yesterday called for the unity government to be formed ``forthwith.''

Zimbabwe is in its 10th year of recession and has the world's highest inflation rate, 231 million percent, following a land-redistribution campaign begun by Mugabe in 2000. The program, in which white-owned commercial farms were seized for redistribution to black farmers deprived of land during colonial rule, slashed agricultural output and led to shortages of basic commodities.

SADC Ruling

The United Nations estimated last month that more than 5 million Zimbabweans, or 45 percent of the population, may need emergency food rations by early next year.

``We cannot afford to postpone the formation of an inclusive government because there is a dispute on who appoints the minister of home affairs,'' Tomaz Salamao, SADC's executive secretary, told reporters. ``Whether the parties agree or not, that's the ruling of SADC.''

The MDC won a majority in parliamentary elections in March. Tsvangirai withdrew from a June 27 presidential runoff vote, citing violence against his supporters, leaving Mugabe to extend his 28-year rule unchallenged.

``We are disappointed that the SADC meeting hasn't been able to resolve the deadlock over the ministries,'' Michael Ellam, U.K. Prime Minister Gordon Brown's spokesman, told reporters in London today. ``The longer there is a delay in appointing a Cabinet, the more difficult it will be for Mr. Mugabe and Zanu-PF to convince the world of their commitment to the Sept. 15 agreement.''

Post-Election Violence

Amnesty International says more than 180 people, mainly from the opposition, have been killed in post-election violence, while more than 9,000 have been injured.

The MDC plans to approach the African Union and the UN to try to salvage the power-sharing accord.

``I doubt the MDC will get much joy from the AU, which usually takes its cue from SADC,'' while China, Russia and South Africa are likely to block any attempt to sanction Mugabe in the UN Security Council, said Brian Raftopoulos, a political analyst at the Cape Town-based Institute for Justice and Reconciliation. ``It's a very difficult position for them.''

SADC's decision that the home affairs ministry should be jointly managed by two ministers wasn't provided for in the power-sharing agreement and wouldn't work, Tsvangirai said. The arrangement would be reviewed after six months, SADC said.

`Unfair Advantage'

``President Mugabe is disregarding the principles of the agreement and is taking an unfair advantage in unilaterally taking decisions that should actually be co-managed,'' Tsvangirai said. SADC ``did not have the courage and the decency of looking Mugabe in the eyes and telling him that his position was wrong.''

Mugabe and Arthur Mutambara, the leader of a splinter MDC faction that also signed the Sept. 15 accord, accepted SADC's ruling, which was accepted by all of its 15 members, including Botswana, a fierce Mugabe critic.

`` We committed ourselves to abiding by the decisions of SADC,'' Mutambara said. ``This was not our desired outcome. Our first preference was for the ministry of home affairs to be given to the party led by Mr. Tsvangirai.''

Mugabe left the summit without commenting to the media.

To contact the reporter on this story: Mike Cohen in Cape Town at mcohen21@bloomberg.net.

Last Updated: November 10, 2008 07:21 EST