President Mugabe's ruling party, the ZANU-PF, and Tsvangirai's opposition party, the Movement for Democratic Change, or MDC, have been in engaged in high-level negotiations over the development of a power-sharing government after months of a bitter and violent dispute over Zimbabwe's presidential election.
"The negotiators are negotiating. As you know they have been meeting here now for a number of days and they are continuing to do that," Mbeki, who is mediating the talks, told reporters in Pretoria. Mbeki said that the break was to give negotiators time to return home and consult with their leaders.
Senior negotiators from ZANU-PF and the MDC started full talks last Thursday.
"They haven't concluded and they [the negotiators] will be adjourning shortly for a couple of days because they want to go to Harare and consult with their principals. And then they will come back at the end of the week," Mbeiki said.
While few details have emerged from the talks, early media reports suggest that the allocation of top government posts could be the reason behind the stall.
"If the sticking points are resolved, then the talks will resume," MDC spokesman George Sibotshiwe told the Agence-France Presse news agency, though he would not provide more details.
The negotiations come after nearly three months of violence that the opposition says left more than 120 dead and forced tens of thousands to flee their homes.
Mugabe was reelected on June 27 in a widely condemned run-off vote, which was boycotted by Tsvangirai because of claims of violence against his supporters.
MDC sources have told media outlets that the Pretoria talks are deadlocked because the opposition party could not accept a proposal to make Tsvangirai a third vice-president, calling the suggesting "insulting," according to the BBC.
Both Tsvangirai and Mugabe are under international pressure to solve the crisis, which has plunged the country into violence, pushed its economy into further crisis and flooded neighboring African countries with Zimbabweans looking for work.
Mugabe's ZANU-PF party has also said that it would not accept any deal that would reverse the land distribution program which, since 2000, has seized thousands of white-owned farms.
Once hailed as an African liberation hero, the 84-year-old Mugabe has been increasingly seen as a dictator, responsible for pushing the country he's ruled for 28 years into political and economic ruin.
The framework agreement for the talks sets a two-week deadline for the government and two factions of the MDC to discuss key issues, including a unity government and how to hold new elections, according to media reports.