"Should it collapse, the MDC will have to find alternative plans to continue with the struggle [for democracy] until the objective is achieved"
"I don't have a credible partner on the part of Mugabe, but we have to deal with him."
Tsvangirai's comments came as the nominee for the next US ambassador to the UN told a senate committee in Washington that the new Obama administration will work to step up pressure on Mugabe.
Speaking at a senate confirmation hearing on Thursday, Susan Rice said she would work for an international campaign to isolate the Zimbabwean president.
"I hope very much that under president-elect Obama's leadership, we will work with southern Africa and bring their private condemnation in to the public sphere ... so that the people of Zimbabwe's suffering can finally end," she said.
|Tsvangirai said a deal was needed to prevent Zimbabwe becoming a "failed state" [EPA]
A power sharing deal between Mugabe and Tsvangirai was signed following disputed elections last year but hit the rocks after parties disagreed over how key cabinet portfolios should be split.
Tsvangirai blames Mugabe's ruling Zanu-PF party for letting Zimbabwe's humanitarian crisis escalate, with food shortages hitting nearly half the population and more than 2,100 people killed in an ongoing cholera epidemic.
He also blamed Mugabe for continuing to arrest opposition supporters, saying it was a breach of a condition in the agreement which guarantees that political parties could operate "free of harassment and intimidation".
On Thursday Human Rights Watch said that 32 opposition members and rights activists had been unlawfully detained, while 11 others were still missing.
Tsvangirai said despite being the ruling party, Mugabe's Zanu-PF "will not do what is necessary" because they lacked the political will.
"The MDC cannot solve the problems because we lack the power," Tsvangirai said. "We need to transfer power from Zanu-PF officials who will not solve the problems, to MDC officials who will."
Tsvangirai also indicated that he was not willing for talks to drag indefinitely, saying that they will have to decide at some point "whether it is worth going into this government or not".
"Should it collapse, the MDC will have to find alternative plans to continue with the struggle until the objective is achieved," he said. "We can't sit back and mourn and regret."