ADDIS ABABA : A prominent Ethiopian opposition leader rejected on Thursday accusations by the regime that he was the mastermind of a plot to assassinate top officials, calling the charges a fabrication.

"They have fabricated the story, as they always do. First they said (it was) a coup, then assassination attempts. They are so used in lying," Berhanu Nega told AFP in a telephone interview from his exile base in the United States.

Ethiopian authorities last week said they had unearthed a plot by senior ex-military officers aligned to the opposition Coalition for Unity and Democracy (CUD) headed by Berhanu to kill top government officials and attack key utility infrastructures.

"It is a set-up. Whenever they panic that is what they do," he said adding the government of Prime Minister Meles Zenawi lacked popular support and "can only govern through crises it creates".

"Of course I don't have a hand in that," added Berhanu, who the government said is "deeply involved" in the conspiracy.

Communications Minister Simon Bereket denied that the government made up the plot.

"It is not a political set up but a criminal offense which the government has ample evidence of," he told AFP.

Bereket last week said the plotters, among them a former army general, belonged to the Ginbot 7 (May 15) opposition group, which he claimed was linked to the CUD.

Forty people have been arrested in connection with the alleged plot and 35 appeared in court for the first time on April 27. The first hearing is scheduled for May 11.

"We don't even know who the people arrested are," said Berhanu.

The government believed that the "desperado" group was not planning to stage a coup, but intended "assassinating individuals, high-ranking government officials and destroying some public facilities and utilities" such as telecom services and electricity utilities.

The idea, Bereket alleged, was "to create conducive conditions for large-scale chaos and havoc".

The CUD won an unprecedented number of seats in the 2005 elections, which the European Union and other observers said fell short of international standards.

Around 200 people died in violence that erupted after the CUD accused Zenawi's party of rigging the ballot.

Berhanu, 51, a university professor in the United States, was elected mayor of Addis Ababa in the polls. He was subsequently jailed for two years along with other leaders of the CUD, and left the country after his release.

But he remains defiant in his criticism of the administration in Addis Ababa, which he alleges seeks a scapegoat for its shortcomings.

"We have said repeatedly that this government put the blame of all its problems on other people.

"But instability is obvious in the country, and they are looking for someone to blame for that," he added.

Berhanu said any attempt to oust the government would be justified because as far as he is concerned the regime is illegal.

"This government is illegal, in power by force through a coup d'etat ... after the elections. Because of that we feel that the society has the legitimacy to rise and overthrow this illegal government," as long as it does not result in civilian casualties, he said.

Berhanu accused the government of staging an ethnic cleansing campaign against the Amhara group.

Ethiopia's next general election is scheduled for June 2010.

But Berhanu said the vote will be a farce.

"What election? Nobody takes that seriously. We'll never have a real election, just a show of election to fool the international community."