Zimbabwean opposition leader Morgan Tsvangirai, who went on trial for treason Monday in Harare, has told British radio he did not plot to assassinate President Robert Mugabe as charged.

Mr. Tsvangirai said he is innocent of charges that he discussed Mr. Mugabe's assassination on a videotape broadcast a year ago.

The tape was shown on Australian television when Mr. Tsvangirai was running for president against Mr. Mugabe, who won an election that was denounced as fraudulent by most Western observers.

Mr. Tsvangirai told British radio the tape was edited to make it look like he was approving a plot to kill Mr. Mugabe. "What has happened is there was a video and there were leading questions from those people. It was not me who was making those proposals. And I responded accordingly, that as far as I'm concerned elimination of Mugabe may lead to another vice president taking over and the elections being held," he explained.

Mr. Tsvangirai said he is not confident he will get a fair trial, describing the process as a "kangaroo court."

The videotape of Mr. Tvsangirai and two associates allegedly shows them discussing Mr. Mugabe's elimination with representatives of a Canadian consultancy firm.

It later emerged that the consultancy was headed by a former Israeli intelligence agent, Ari Ben Menashe, with close ties to Mr. Mugabe's political party.

The Tsvangirai trial begins at a delicate time for Zimbabwe, just 10 days ahead of a series of World Cup cricket matches there that have focused attention on its security and human rights situation.