"This crisis is going to be resolved through negotiation and [the ruling] ZANU-PF and MDC will sit down and negotiate," he said.
On Thursday Tsvangirai accused state security agents of being part of "hit squads" that abducted and tortured 600 activists in the past three months.
He said 150 MDC activists and leaders had suffered life-threatening injuries since February 16.
President's backing
"This programme, which is directed, sanctioned and supervised by Robert Mugabe himself, is being carried out by mixed hit squads, comprising the police, CIO [Central Intelligence Organisation] and militias," Tsvangirai said.
Mugabe's government says the MDC has launched a violent campaign, including petrol bombing police stations and attacking ruling party officials, to topple the 83-year-old ruler.
Tsvangirai rejected those charges on Thursday.
Tsvangirai was among dozens of anti-Mugabe activists who were arrested at an aborted March 11 prayer rally in Harare.
Reports that the MDC leader and his colleagues had been savagely beaten prompted sharp international protests.
The MDC has repeatedly said that security agents and police harass, beat and murder its members.