The coalition has stalled over a lack of political progress, the MDC asserts
Zimbabwe's Morgan Tsvangirai has ended talks on power-sharing with President Robert Mugabe with no agreement, a spokesman for the prime minister says.
The four-hour meeting is the first time the prime minister has met with the president since pulling out of the coalition government on 16 October.
A spokesman for Mr Tsvangirai said both men were "worlds apart" on many issues.
Mr Tsvangirai withdrew from a coalition over political stalemate and charges brought against a senior MDC member.
"The principals met. Sadly and tragically the stalemate continues," said Nelson Chamisa, spokesman for Mr Tsvangirai's Movement for Democratic Change (MDC).
"We are worlds apart on fundamental issues," he added.
Prior to the talks, a spokesman for President Mugabe had described the dialogue as a "normal meeting", something that Mr Tsvangirai's camp had strenuously denied.
The MDC, which was in opposition in Zimbabwe for many years, says it is now looking to a meeting in Harare later in the week of the Southern African Development Community (SADC) to try to break the deadlock.
"If that fails... a free and fair election under the supervision of the international community, SADC and the African Union will be the only option," Mr Chamisa said.
"If they [Mr Mugabe and the Zanu-PF] are facing west we are facing east," he added.
Relations between the partners in the unity government have soured considerably in the past few days, says the BBC's regional correspondent, Karen Allen.
Mr Tsvangirai walked out of a coalition government in protest at the detention of a senior MDC aide on terrorism charges and over Mr Mugabe's refusal to implement political agreements, reports say.
The aide, Roy Bennett, was later released on bail.
A raid on an MDC office at the weekend is being viewed as a further attempt at intimidation by Zanu PF, our correspondent adds.