HARARE, Sept 12 (Reuters) - Zimbabwe's power-sharing deal faces a tough credibility test to determine whether it is enough to kick start the country's emergence from catastrophic economic collapse.
President Robert Mugabe and opposition leader Morgan Tsvangirai agreed to share power on Thursday in a pact ending a deep political crisis compounded by the veteran leader's disputed and unopposed re-election in June.
Analysts say the agreement is only a fragile first step and will require former enemies to put aside their differences and work closely to overcome scepticism, especially from Western powers whose support will be vital for recovery.
"It's going to be like walking out of a landmine field while carrying a huge load," said Eldred Masunungure, a political science professor at the University of Zimbabwe.
"The deal will only survive on a lot of goodwill, commitment and strategic thinking by all the key players because it can easily collapse even on small things and misunderstandings," he said.
Initially the MDC opposition will be anxious to ensure that it has its hands on some levers of power, and that Mugabe is not merely trying use it as cover to win back international approval and vital financial aid to rescue an economy mired in the world's worst inflation -- over 11 million percent.
Key foreign donors, who have promised a massive rescue package if democracy is restored, are likely to take a cautious approach.
The European Union on Friday welcomed the deal as a step forward and said it was rethinking plans to extend sanctions against Mugabe's government.
But it said it needed to see the detail before making a final decision, as did former colonial power Britain.
Mugabe and Tsvangirai have been sworn rivals for over a decade, and analysts say they will both have to demonstrate that they are committed to working together and sharing power.
"The real test is ahead, and that's what's going to determine whether the international community comes on board to help the country economically," Masunungure said.
Right up until Thursday, Tsvangirai's officials had said agreement was blocked by Mugabe's refusal to give up executive powers. The former guerrilla commander, 84, said Tsvangirai wanted to strip him of all authority.
Full details of the deal have not been released but David Coltart, a senator for a small breakaway faction of the MDC, said Mugabe would remain as president and chair the cabinet but the combined opposition would have one more seat on it than ZANU-PF.
South African President Thabo Mbeki, who mediated the deal, said details would not be announced until a ceremony on Monday.
There is scepticism among analysts about how much real power Mugabe has surrendered to Tsvangirai -- whom he was still labelling a Western stooge just hours before the deal was announced.
"The fact that Mugabe remains in power as head of state and head of government means the MDC is the one coming into this deal as a junior partner," said Lovemore Madhuku, head of the pressure group National Constitutional Assembly.
Political commentator and Mugabe critic John Makumbe said: "I think the challenge is on Mugabe to make this work because he is the one who has problems with the world, the one with a big credibility gap.
"Mugabe will be watched like a hawk both at home and from abroad."
Makumbe said Tsvangirai -- a former trade union leader whose party has survived a ruthless government crackdown -- may have agreed a less than desired deal with Mugabe to rebuild the economy so the MDC can win the next elections.
"He is young, and if the international community gives him support and the economy takes off, the voters will give him that credit," he said of the 56-year-old Tsvangirai.
In elections last March, ZANU-PF lost its parliamentary majority for the first time since independence from Britain in 1980, but Tsvangirai's MDC did not win an outright majority. The balance of power rests in the hands of the breakaway opposition faction led by Arthur Mutambara.
John Robertson, a leading Zimbabwean economic consultant, said Western investors would take their time to assess the political environment and see the unity government's policies.
"There is not going to be a stampede ... and without a change in some of the current policies, we are also not going to see much money coming our way," he told Reuters.
Analysts say Zimbabwe's economy -- which critics accuse Mugabe of destroying by seizing white-owned commercial farms and giving them to inexperienced black farmers -- will get worse without foreign assistance and investment.
Robertson said Tsvangirai would have to persuade Mugabe to quietly drop or reform some of his radical nationalist policies, including plans to transfer control of foreign-owned businesses, including banks and mines, to locals.
"The future really is in how much Mugabe is willing to change," he said.
Roelof Horne, an asset manager at Investec shared reservations about how optimistic to be over the deal, saying the architects of Zimbabwe's economic meltdown would still be partly in the driving seat.
"The Zimbabwean economy needs more than peace. It needs generosity from outside and austerity from within...Unless my expectations are exceeded, I am afraid the economic road will be a muddle-through and not a victory march," he said. (Editing by Barry Moody)
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