Zimbabweans remained in suspense on Friday for the sixth day following the country's March 29 elections, with the winner of the presidential ballot still unannounced by the Zimbabwe Electoral Commission while the leadership of President Robert Mugabe's ZANU-PF party endorsed his candidacy in a possible runoff contest.

The Movement for Democratic Change formation led by Mr. Mugabe's likely opponent in such a runoff, Morgan Tsvangirai, continued to insist that Tsvangirai had polled more than 50% in the first round, obviating the need for a runoff ballot.

Officials of Tsvangirai's MDC grouping accused ZANU-PF of launching a campaign of violence and intimidation around the country following the former ruling party's loss of its majority in the lower house of parliament. Tsvangirai's formation combined with the rival MDC faction of Arthur Mutambara have officially claimed a house majority.

Amidst impatience on all sides, the electoral commission released further results of the senate election, giving ZANU-PF 21 seats (including an uncontested senate seat), the Tsvangirai MDC grouping 19 seats and the Mutambara MDC 4 seats. That left 16 seats out of the total of 60 senate seats to be announced, possibly Saturday.

Tsvangirai met with diplomats and said his party would closely scrutinize presidential ballots as they were counted thus an official result seemed unlikely before Tuesday.

His party continued to assert that Tsvangirai took 50.3% of the first-round ballots.

But ZANU-PF officials continued to insist no winner had emerged. Its politburo met for a marathon session after which it endorsed Mr. Mugabe for a possible runoff. Some in the former ruling party had expressed fears of a second-round Tsvangirai landslide.

ZANU-PF sources said some politburo members urged Mr. Mugabe to delay a runoff for 90 days from the first round, though the law says it must be held in 21 days.

Meanwhile the political temperature was rising. Liberation war veterans supporting Mr. Mugabe took to the streets and the leader of the main veterans group, Jabulani Sibanda, alleged outside interference in Zimbabwe's internal affairs.

The politburo also resolved to challenge parliamentary results in some constituencies that it had narrowly lost in the first election round.

From Harare VOA correspondent Thomas Chiripasi reported that opposition leader Morgan Tsvangirai expressed disappointment with the continuing delays.

U.S. President George Bush on Friday reached out to South African President Thabo Mbeki seeking an assessment of the situation in Harare, the White House said. Bush spoke to Mbeki from aboard Air Force one en route to Croatia from Romania.

"Our position is to counsel against violence," White House press secretary Dana Perino said. "We believe people should wait for the election results and when the announcement is made, that people respect the outcome," Perino added.

Mbeki, speaking to reporters following a session of a bilateral commission for affairs concerning South Africa and the Democratic Republic of Congo, urged patience.

But fears grew as delays stretched that the presidential outcome might be rigged.

Political analyst and human rights lawyer Dewa Mavhinga told reporter Blessing Zulu of VOA’s Studio 7 for Zimbabwe that ZANU-PF's move endorsing Mr. Mugabe for a runoff looked suspicious as the presidential results have not been announced.

More reports from VOA's Studio 7 for Zimbabwe...