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By Daniel Flynn
MALABO, June 18 (Reuters) - The son of former British Prime Minister Margaret Thatcher was a leader of a 2004 coup plot in oil-rich Equatorial Guinea that was backed by Spain and South Africa, a British mercenary told a court on Wednesday.
Former special forces officer Simon Mann testified that Mark Thatcher was "not just an investor" in the plot to oust Equatorial Guinea President Teodoro Obiang Nguema Mbasogo, who has ruled the West African state since 1979.
Mann, one of the defendants in the coup trial, identified Thatcher as one of a five-man group headed by London-based Lebanese millionaire Eli Calil, whom he said masterminded and bankrolled the conspiracy.
"He (Thatcher) came on board completely and became part of the management team," Mann told the court in the island capital.
He added Thatcher invested some $350,000 in the March 2004 operation, which was foiled when authorities in Zimbabwe arrested Mann and 70 mercenaries at Harare airport en route to Equatorial Guinea aboard a Boeing 727.
Public Prosecutor Jose Olo Obono told Reuters the next step after the trial, likely to end next week, was to seek the extradition of Thatcher and Calil. Both men deny involvement.
Mann, 56, said the governments of South Africa and former colonial power Spain knew and approved of the conspiracy to replace Obiang with exiled opposition leader Severo Moto.
Spain's Foreign Ministry quickly issued a denial.
In the first day of Mann's trial on Tuesday, prosecutors asked the court to jail him for nearly 32 years for his role in the conspiracy. His defence lawyer said he was an "instrument", not a ringleader, and called for a shorter sentence.
"All of this was going on under Eli Calil's control. He was the boss," Mann, looking gaunt in his grey prison uniform, told the courtroom, which was guarded by heavily-armed soldiers.
"I am very, very sorry for what I have done. I am also very happy that we failed," said Mann, who was educated at exclusive private school Eton, where Britain's Princes Williams and Harry were later students. Mann has said he hopes for clemency from Obiang after already serving a four year jail term in Zimbabwe.
"The people that were seriously involved in this and have not faced justice, they should do so." Mark Thatcher, arrested in 2004 by South African police, said he thought he was financing an air ambulance service. He was released after pleading guilty to breaking South Africa's anti-mercenary laws and he paid a $450,000 fine.
"GREEN LIGHT" FROM SPAIN, SOUTH AFRICA
Mann testified on Wednesday that during a series of meetings in Madrid in 2003 with Calil and Moto, the Lebanese businessmen had assured him the coup had the support of the centre-right government of Spanish President Jose Maria Aznar.
Mann said the plotters had rushed to try to carry out the coup before March 14, 2004. This was the date of a general election in Spain which they feared would change the government and deprive them of the Spanish diplomatic recognition and a contingent of Spanish civil guards he said they were promised.
"By January 2004, the operation was like an official operation because the Spanish government and the South African government were both giving the green light," Mann said.
Aznar stood down at the 2004 polls but his Popular Party was defeated three days after a Muslim militant train bombing in Madrid killed 191 people.
A Spanish Foreign Ministry spokesman in Madrid rejected the allegations: "We did not give the green light to any of this."
Mann said an intelligence contact, Nick Morgan, who liaised with South Africa's intelligence services, had assured him that Pretoria also approved of the coup bid. He even asked Mann to provide Moto's telephone number so that South African President Thabo Mbeki could call Moto if the coup succeeded. The prosecution said Calil, who made his fortune in Nigeria's oil sector, invested some $2 million in the coup attempt and was its main financier.
Mann said Calil had originally asked him to assassinate President Obiang, but he had refused. Calil had also suggested the coup would receive support from senior military and government officials in Equatorial Guinea, Mann testified.
He said he had agreed to participate in the coup in sub-Saharan Africa's third largest oil producer in part because its oil wealth was not reaching its population, estimated at 600,000. Equatorial Guinea was ranked as the 10th most corrupt country in the world last year by Transparency International.
"I agreed to do this for the money, yes, but also because I believed it was right," Mann said.
The trial continues. (For full Reuters Africa coverage and to have your say on the top issues, visit: africa.reuters.com/) (Additional reporting by Ben Harding in Madrid; Editing by Pascal Fletcher and Matthew Jones)