A spokesman for Zimbabwe’s Movement for Democratic Change (MDC) on Tuesday expressed regret that the party signed a power-sharing deal with President Robert Mugabe, without having agreed on the make-up of a unity government.

Speaking on South African radio about the three-week delay in the implementation of the historic September 15 agreement, MDC spokesman Nelson Chamisa said he he thought the party’s “big mistake” was to have signed a deal before the negotiations had been concluded.

Hopes for an end to Zimbabwe’s economic and political crisis had been high when autocratic President Robert Mugabe agreed to share power with his longtime rival Morgan Tsvangirai in a deal brokered by former South African president Thabo Mbeki.

Under the deal, Mugabe remains president with reduced powers and Tsvangirai becomes prime minister.

Three weeks later, fears that the deal could fall apart are mounting as Mugabe’s Zanu-PF party and the MDC remain at loggerheads on how to share ministerial posts between them.

The bare-bones September agreement merely states that Zanu-PF is to get 15 ministries in a 31-ministry cabinet, Tsvangirai’s MDC is to get 13 and a splinter MDC faction led by Arthur Mutambara gets three.

Despite widespread reports before the signing that the parties had agreed that the MDC would gain control of key ministries such as home affairs, which controls the police, and finance, and that Zanu-PF would retain defence, among others, the MDC says there was never any such agreement.

Early last week, Mugabe had said he expected the government to be finalized by the weekend and that only four ministries were still in contention. But later talks between the 84-year-old leader and Tsvangirai, 56, ended without a breakthrough.

Accusing Zanu-PF of wanting to retain its stranglehold on power, the MDC has referred the disagreement to the Southern African Development Community, which deployed Mbeki as a mediator.

“We are very clear that there hasn’t been any progress,” Chamisa said.

“Zanu-PF are resorting to propaganda, misinformation, misleading the public, trying to portray a kind of picture where things are moving,” Chamisa accused.

Since the agreement, Mbeki has been ousted by the ruling African National Congress as South Africa’s president.

SADC has endorsed him to remain on as mediator in Zimbabwe, but Mbeki has not yet returned try to shore up the deal, which is seen as crucial to salvaging Zimbabwe’s battered economy.

Western governments are standing by to inject millions of dollars of aid and investment into Zimbabwe but only if a credible MDC-dominated government is installed.