At a press conference in South Africa on Monday, Arthur Mutambara, the leader of the second faction of the MDC, said: "There will be no division amongst ourselves vis-a-vis the resolution of the Zimbabwean crisis.
"I'm here to show solidarity to the winner of the presidential election in Zimbabwe," he said, referring to Tsvangirai.
The two MDC factions together control 109 seats against Zanu-PF's 97 seats, according to results from the March 29 elections.
A partial recount of results by Zimbabwe's electoral commission confirmed the opposition has a parliamentary majority.
Utoile Silaigwana, a spokesman for Zimbabwe's electoral commission, said recounts for five remaining constituencies were being collated and would be available on Tuesday.
"Once this process has been completed, the process of verification of the presidential ballots will also commence tomorrow," he said.
Tsvangirai has also proclaimed himself the winner of the presidential election held on the same day and said that Mugabe should concede the presidency.
Results from the presidential vote have still not been released by the authorities.
But an election official said on Monday that verification of results from the presidential polls will start on Tuesday.
At the press conference in Johannesburg, Tsvangirai called on the United Nations to "send a special envoy to investigate this violence and recommend a way to resolve the issue".
"What has transpired is a militarisation of our country. We have requested that the UN must deal with this matter," he said.
|The UN says it is alarmed over |
post-election violence [AFP]
The MDC says at least 15 people have been killed and scores more have been arrested since the presidential poll.
In a counter claim, Zanu-PF said one man was killed and two others were injured when MDC supporters tried to attack an army training camp, a state newspaper said on Tuesday.
Quoting a government statement, the online version of The Herald newspaper said the incident took place in a rural district in eastern Zimbabwe but gave no details of when it happened or the identities of the casualties.
On Sunday, Louise Arbour, the UN's senior human rights official, expressed alarm over post-election violence that she said could undermine efforts to overcome the country's political crisis.
"I am particularly concerned about reports of threats, intimidation, abuse and violence directed against NGOs, election monitors, human rights defenders and other representatives of civil society," Arbour said in a statement released in Geneva.
"The information I have received suggests an emerging pattern of political violence inflicted mainly, but not exclusively, on rural supporters of the opposition MDC party," she said.
"If serious and systematic human rights violations persist, they will undermine national and regional attempts to defuse the present political crisis," Arbour added.
Mugabe accuses his critics of plotting with Western nations to end his 28-year rule.
Zimbabweans face severe shortages of basic goods and an inflation rate of 165,000 per cent - the world's highest.