FACTBOX: What next in Zimbabwe's political crisis?

HARARE (Reuters) - Zimbabwe's President Robert Mugabe and MDC opposition leader Morgan Tsvangirai have failed to agree on a power-sharing government after three days of talks in Harare.

South African President Thabo Mbeki said agreement had been reached between Mugabe and breakaway MDC faction leader Arthur Mutambara.

Below are some questions and answers on Zimbabwe's political uncertainty.

WHAT DEAL HAS BEEN DONE?

It is still unclear. Although Mbeki said agreement had been reached with Mutambara, he was unsure whether anything had been signed. A top official of Mugabe's ZANU-PF party said it had been signed, but a spokesman for Mutambara's faction of the Movement for Democratic Change denied that.

WHAT COULD AN INCOMPLETE DEAL MEAN?

Political analysts say such an agreement would not end Zimbabwe's post-election political crisis and is likely to damage confidence further in an economy groaning under the world's highest inflation rate of 2.2 million percent.

Lack of a unified political leadership could make it even harder to ease chronic food, fuel and foreign currency shortages and rescue a virtually worthless local currency.

IS THERE A CHANCE FOR A COMPREHENSIVE DEAL?

Mbeki said he was confident a solution was possible and Tsvangirai was still considering his position. The South African leader said he was willing to stay in Zimbabwe for six months to help reach a settlement.

The magnitude of the divisions may become clearer when Mbeki briefs a weekend summit in South Africa of the regional group of nations SADC, which mandated him to mediate.

WILL TALKS RESUME SOON?

Mugabe's ruling ZANU-PF party and MDC negotiators are expected to return to South Africa for secret talks to try to iron out outstanding issues.

WHAT ARE MUGABE'S PLANS?

Mugabe, in power since 1980, is expected to convene parliament next week, and appoint a cabinet that includes some opposition figures, possibly including some from Tsvangirai's mainstream MDC.

Mugabe's aides say the government must continue functioning, but the formation of a new cabinet could scupper or delay further talks with the opposition.