HARARE, May 30 - Zimbabwe’s ruling Zanu-PF party should be reformed, opposition leader Morgan Tsvangirai said in a speech that may open the door to a national unity government.

Tsvangirai’s Movement for Democratic Change won the March 29 parliamentary election with a slim majority, handing Zanu-PF its worst defeat since President Robert Mugabe led it to power after independence from Britain in 1980.