He did not mention the former South African leader by name, but referred to a "facilitator".
"We have declared a deadlock and therefore the process cannot move forward except in the presence of the facilitator ... We have asked him to come over and he has said he will come over," he said.
Mbeki's spokesman was not immediately available for comment.
Tsvangirai's comments came more than three weeks after the power-sharing deal was signed.
"It's clearly an indication that there is no movement," Nelson Chamisa, the spokesman from Tsvangirai's MDC party, told Al Jazeera.
"There is a deadlock on the key, outstanding issues - namely the issue of cabinet ministries or posts, as well as the issue of governors"
Movement for Democratic Change spokesman
"There is a deadlock on the key, outstanding issues - namely the issue of cabinet ministries or posts, as well as the issue of governors," he said.
"To unlock that impasse and lack of progress we need a helping hand ... by way of Sadc [the South African Development Community] and the African Union."
Tsvangirai defeated Mugabe in a first round of presidential voting in March, but pulled out of a June run-off, accusing the Zanu-PF of violence against his supporters.
Mugabe, Tsvangirai and Arthur Mutambara, the leader of a breakaway MDC faction, signed a power-sharing deal, brokered by Mbeki, on September 15.
Under the agreement brokered by Mbeki, Mugabe remains as president while Tsvangirai takes the new post of prime minister.
But efforts to form the government have bogged down over disputes about who will control the most important ministries, such as defence, home affairs and finance.
"On the day we signed the agreement, the people of Zimbabwe breathed a sigh of relief and their hopes for a final resolution of this crisis were raised." Tsvangirai said.
"Unfortunately no progress has been made since then to bring the Zimbabwean people to the beginning of the path of recovery. Instead the economic crisis has worsened."
State media announced on Thursday that Zimabwe's inflation rate had soared to 231 million per cent in July - the highest in the world.
The United Nations estimates that nearly half of the population will need food aid, with 80 percent of the population living in poverty.