Three days after Zimbabweans went to the polls to vote on President Robert Mugabe's 28-year rule, the opposition Movement for Democratic Change (MDC) was in talks with the ruling Zanu-PF party, a source close to the MDC said Tuesday.

Earlier, Britain's Guardian newspaper also quoted an unnamed senior source within the MDC as saying the party was in touch with senior members of the military.

News of the talks fuelled speculation that the country's election commission, which has been releasing results from Saturday's elections at a snail's pace was trying to buy time until some sort of agreement was struck.

Further stoking the speculation of behind-the-scenes developments was the repeated scheduling and later cancelling of press conference by MDC leader Morgan Tsvangirai in Harare throughout the day.

Mugabe's rule looks increasingly tenuous after an independent estimate showed him coming in second behind Tsvangirai.

The estimate, produced by the Zimbabwe Election Support Network, shows Tsvangirai taking 49.2 percent of the vote against 41.8 percent for Mugabe and 8.2 percent for a third candidate, former finance minister Simba Makoni, who ran as an independent.

If reliable, it could mean that Tsvangirai and Mugabe would enter a runoff vote, as provided for in the constitution if neither candidate takes more than 50 percent of the vote.

It was not clear whether either party would entertain a runoff. Mugabe ruled it out directly after the election saying it would "not be necessary". He has also vowed to respect the wishes of Zimbabweans in the polls.

The trickle of official results from the parliamentary elections that were held concomitantly with presidential and local elections Saturday showed the MDC enjoying a slight lead over Mugabe's Zanu-PF party.

With over half the 210 seats in the House of Assembly (lower house of parliament) counted, Zanu-PF had 64 seats against 67 for the MDC. Of the MDC, vote 62 went to Tsvangirai's larger faction of the divided party and five for a smaller, breakaway MDC faction led by Arthur Mutambara, the Zimbabwe Electoral Commission said.