Mr Tsvangirai on Friday returned from a trip to urge neighbouring leaders to
act to prevent Zimbabwe
sliding back to the "dark days" of violence seen in the disputed
2008 elections which saw him form a coalition with his rival Mr Mugabe.
On Saturday, he is due to address a Movement for Democratic Change rally in
Harare, defying a police order that it be cancelled.
Diplomatic sources in Harare said they feared the rally, which will take place
close to a meeting of Mr Mugabe's Zanu PF supporters, could end in bloodshed
if police intervene.
There are also concerns that Zimbabwe's Joint Operations Command, made up of
the heads of the police, armed forces and state security, could use the
opportunity to arrest Mr Tsvangirai, who was last week accused of contempt
of court for accusing the country's senior judges of political bias.
Sources have told The Daily Telegraph that Mr Mugabe, 87, is becoming
increasingly frail and defers decisions to his closest advisers - mostly
members of the JOC.
Mr Tsvangirai said it was clear his old political foe and now coalition
partner had lost control.
"It appears the civilian authority is no longer in charge and dark and
sinister forces have engaged in a hostile takeover of running the affairs of
the country, with or without the blessing of some leaders of the civilian
authority," he said.
A diplomatic source said today's rally could be the climax to the recent
unrest, which has seen around 100 MDC activists arrested.
"If the MDC does go ahead with it as it says it is going to, there could
well be trouble," he said. "The police may let it go ahead because
they want an excuse to crack down."
