Robert Mugabe, the president of Zimbabwe, has said that any top official or civil servant who plots against him will face dismissal and prosecution.

Mugabe spoke on Thursday at a ruling ZANU-PF party congress at which he was expected to consolidate his grip on power by appointing a new set of loyalists, including his wife Grace.

"Those who committed the crime and corruption will be prosecuted once we get the evidence," the 90-year-old leader said. "Even if you are a government minister, deputy minister or a civil servant, you will be fired." 

‎Over the years, several ‎people have been accused of trying to unseat President Mugabe...So far, no one has succeeded. Mugabe has always managed to survive.

Haru Mutasa, Al Jazeera correspondent reporting from Harare

Vice President Joice Mujuru did not attend the meeting at which Mugabe spoke. Mugabe has sharply criticised Mujuru, signalling that that she is no longer a favourite to succeed him.

The state-run Sunday Mail newspaper has alleged that Mujuru was involved in an assassination plot against Mugabe, who has been in power since independence in 1980.

Mujuru denies the allegations, saying she is prepared to defend herself in court.

Mugabe supporters had said they would bar Mujuru and her political allies from attending, the Associated Press news agency reported.

One political analyst said the political manoeuvring indicates that Mugabe wants to be president for the rest of his life and also seeks to protect the economic interests of his family.

"You challenge Mugabe, you are accused of treason," Pedzisai Ruhanya, who runs the Zimbabwe Democracy Institute, a research group, told AP.

'Nonsense' allegations

Rugare Gumbo, a Mujuru supporter who was recently ousted as a ruling party spokesman, said he had worked long enough with Mugabe to know his political tactics.

"If he wants to destroy someone, he will just say you want to assassinate him," Gumbo said.

"This nonsense about us trying to assassinate the president - that's a trick that we have known from the liberation struggle."

Despite his old age and rumours of cancer, Mugabe is running unchallenged as ZANU-PF leader.

After his speech, Mugabe stood on the podium decked out in a bright yellow jacket and baseball cap, swaying gently from side-to-side and clapping to the rhythm of a jazz band, the Reuters news agency reported.

Assuming he is still fit and able, he will be ZANU-PF's leader when the next elections come round in 2018.

‎"Over the years, several ‎people have been accused of trying to unseat President Mugabe. There was Joshua Nkomo, Edgar Tekere, Morgan Tsvangirai, Simba Makoni and now Joice Mujuru,"  Al Jazeera's Haru Mutasa, reporting from the capital, said.

"So far, no one has succeeded. Mugabe has always managed to survive."

Mugabe's wife Grace is expected to become the head of the powerful ZANU-PF Women's League, giving her a seat on the party's politburo, its top decision-making body.

Source: Al Jazeera and agencies