Heads of Southern African Development Community (SADC) states meeting in Kinshasa, Congo had been due to discuss the months-long political and economic crisis in Harare, but the issue was pulled from the agenda at the last moment.
"Zimbabwe is not on the agenda. It is clearly not on the agenda," Tsvangirai spokesman James Maridadi told reporters at a two-day meeting in the Congolese capital attended by President Robert Mugabe and Tsvangirai.
"It will need its own extraordinary summit," he added, not elaborating on when and where the meeting would take place.
Mugabe and long-time foe Tsvangirai formed a power-sharing government in February as part of a SADC-backed deal to end a political crisis that followed disputed polls last year.
But the power-sharing deal is beset with problems.
Tsvangirai’s MDC party accuses Mugabe’s ZANU-PF of failing to honour a pact to reverse the appointments of political allies to key posts. ZANU-PF, in turn, has charged that the MDC has not done enough to have EU and U.S. sanctions on Mugabe lifted.
Earlier South African President Jacob Zuma stepped up pressure on them to end their row over the power-sharing pact, a move that would release vital foreign aid to its battered economy.
"We urge all parties to remove any obstacles to the implementation of the agreement," Zuma told the meeting.
Zuma is being closely watched at the conference for signs he will take a tougher line than predecessor Thabo Mbeki over Mugabe, who faces travel bans and asset freezes in the West as punishment for alleged human rights abuses and vote-rigging.
Last month, Zuma urged an end to the sanctions but also stressed the need for respect of democracy and human rights — a comment interpreted by some as directed at Mugabe. However his speech at the opening ceremony in Kinshasa made no mention of the sanctions nor any direct reference to Mugabe.
Earlier, summit host Congo said it was confident the meeting would culminate in a call for an end to the sanctions.
"We are convinced that if sanctions are lifted, Zimbabwe, within the framework of its current political agreement, will have the possibility to move towards development," said Congolese Foreign Minister Alexis Thambwe Mwamba.
A recovery in Zimbabwe’s battered economy is important for South Africa because millions of Zimbabweans have been driven to seek work in their much wealthier neighbour. Zimbabwe says it needs $10 billion in foreign reconstruction aid, but Western nations are reluctant to release aid without political and economic reform.