President Robert Mugabe of Zimbabwe said Thursday that any top official or civil servant who plots against him will face dismissal and prosecution.

Mugabe spoke at a ruling ZANU-PF party congress at which he is 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."

Vice President Joice Mujuru did not attend the meeting at which Mugabe spoke. Mugabe has sharply criticized Mujuru, which underscores that she is no longer a favorite 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.

Other officials who were not present during Mugabe's speech included Didymus Mutasa, the presidential affairs minister, and Labor Minister Nicholas Goche. Mugabe supporters had said they would bar Mujuru and her political allies from attending.

One political analyst said the political maneuvering 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," said Pedzisai Ruhanya, who runs the Zimbabwe Democracy Institute, a research group.

Rugare Gumbo, a Mujuru supporter who was recently ousted as 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 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."