(CNN) -- Zimbabwe's main opposition party has accused the government of President Robert Mugabe of orchestrating a plot to assassinate its leader Morgan Tsvangirai.
Morgan Tsvangirai won 47.9 percent of the presidential vote, according to official results.
Tendai Biti, secretary-general of the opposition Movement for Democratic Change, told CNN that Zimbabwe's military intelligence directorate was behind the plot. He offered no further details.
Tsvangirai canceled his return to Harare from South Africa on Saturday, after receiving information from a "credible source" about a planned assassination, his spokesman said Saturday.
When contacted by CNN, a Cabinet member denied that the government had any possible role in the alleged plot, and said the report was an effort by the MDC to gain international sympathy.
Tsvangirai's spokesman George Sibotshiwe said Saturday that the opposition leader "is not the only person under threat at the moment."
"The entire leadership of the MDC, leaders of democratic forces within the country and every Zimbabwean is at risk from this brutal regime," he said.
Chen Chimutengwende, Zimbabwe's minister of public and interactive affairs, accused Tsvangirai of "trying to paint a false picture of what Zimbabwe and Zimbabwe authorities are like."
"There is no plot against him and there has never been any plot against him and he knows that," Chimutengwende said.
He called the reports from Tsvangirai's party "an effort to get sympathy from the international community."
Tsvangirai won more votes than Mugabe in the presidential election on March 29, but he did not garner enough votes to avoid a runoff, now set for June 27.
The MDC contends Tsvangirai won the election with 50.3 percent of the vote, giving him the necessary majority. The party argued that the Electoral Commission, which delayed publicly releasing the results for weeks, fudged the numbers to protect Mugabe, who leads the Zanu-PF party.
According to Chimutengwende, Tsvangirai "knows he is unlikely to win" the second round of voting.
Since the March balloting, the MDC and church groups have reported kidnappings, torture and other violence, including the deaths of 25 opposition party members.
They say the violence has targeted opponents of Mugabe and his Zanu-PF party. Mugabe has ruled the southern African country since it became independent 28 years ago.
"The level of violence in this country is not the kind of violence that can stop an election from going ahead," and it cannot all be blamed on the Zanu-PF, Chimutengwende said.
Sibotshiwe said Tsvangirai, now in Johannesburg, was determined to go home as soon as possible, once security arrangements were settled.
Party members were consulting Southern African Development Community officials on the security issue, and once those talks end, a date for Tsvangirai's return would be set, Sibotshiwe said.
"It should be remembered that the political stakes in Zimbabwe have never been higher," Saturday's statement said.
"The wave of violence unleashed by Zanu-PF since the MDC won both the parliamentary and presidential elections showed that they are desperate to retain their illegitimate hold on power, and are willing to go to any length to do so."
CNN correspondent Nkepile Mabuse contributed to this report.
All About Zimbabwe • Robert Mugabe • Morgan Tsvangirai