Zimbabwean Prime Minister Morgan Tsvangirai on Tuesday called for peace and demanded political reforms before any election to replace a coalition government with his long time rival President Robert Mugabe.

"There must be a non-violent environment so that people vote in a free and fair vote," Tsvangirai said while addressing hundreds of workers marking Workers Day at Gwanzura stadium in Harare.

"Elections must not reproduce the 2008 scenario where Tsvangirai wins but cannot form a government, that we will not accept."

"This unity government must be ended by a process which was agreed by SADC (Southern African Development Community), there must be a new constitution, there must be a referendum, a new voters roll," he added.

Tsvangirai and Mugabe formed a coalition government in February 2009 after a disputed presidential poll run-off in June 2008.

Tsvangirai, who won the first round of the vote in March 2008 pulled out of the run-off citing violence against his supporters.

The prime minister's Movement for Democratic Change has said over 200 supporters and officials of the party were murdered during the presidential run-off. The party blamed the violence on Mugabe's ZANU PF party.

Mugabe who has ruled the country since 1980 when the country won its independence continues to insist that elections will be held this year while Tsvangirai says reforms are a condition to guarantee a free and fair vote.

The southern African country is currently drafting a new constitution which will go to a referendum before elections according to the political agreement brokered by SADC to form a coalition government.