Zimbabwe's ruling party and opposition have been unable to reach a power-sharing agreement at a regional summit of Southern African leaders.
However, South African President Thabo Mbeki said after the official summit closed that talks would continue.
The secretary-general of Zimbabwe's opposition MDC said on Sunday that he believed a power-sharing deal with the country's ruling party would be reached soon.
Tendai Biti told a news conference in Johannesburg that the MDC was committed to the negotiations and failure was not an option.
A troika of Southern African leaders called on Zimbabwe's ruling party and opposition to quickly reach a power-sharing agreement and said parliament may have to be convened as talks continue.
The Southern African Development Community's security, political and defence committee called on the parties to wrap up the talks "as a matter of urgency".
