U.S. Secretary of State Condoleezza Rice is calling for Zimbabwe's neighbors to step up and press for an end to that country's post-election political crisis. Rice said it is time for Zimbabwe to move on after years of mis-rule by the government of President Robert Mugabe. Meanwhile, Zimbabwe's opposition leader is calling for South African President Thabo Mbeki to stop mediating Zimbabwe's crisis. VOA's David Gollust reports from the State Department.

U.S. officials had been privately expressing disappointment with the seeming lack of commitment by southern African countries on the Zimbabwe crisis.

But Rice, in a news conference here, took U.S. concerns public, saying regional organizations like the African Union and the Southern African Development Community need to take the lead in pressing for the release of presidential election returns in Zimbabwe, and if necessary a peaceful transition of power.

"The longer they hold the results of the election, the more suspicion grows that something is being plotted and planned by the ruling party. And frankly the United States and the European Union and others have spoken out about this and made calls," said Rice. "But it is time for Africa to step up. Where is the concern from the African Union and from Zimbabwe's neighbors about what is going on in Zimbabwe."

Rice said U.S. concerns about the situation have been heightened by new accusations of treason by the Mugabe government against opposition presidential candidate Morgan Tsvangerai, who claims he won the March 29 election.

Rice stopped short of flatly calling for the departure of President Mugabe, who has run the country since independence. But she used her strongest language to date to characterize his administration.

"Obviously this is a matter for Zimbabwe as to whether he steps down. But I think he has done more harm to his country than would have been imaginable, if you look at what Zimbabwe was 15 just years ago or so," said Rice. "I know the role that he played in liberation of Zimbabwe, but the last years have really been an abomination."

Rice said Zimbabwe, once a food exporter, will apparently be requiring a dramatic increase in food aid from the international community.

She described Zimbabwe as "a country that really needs to move on, and get on with its future."