Mark Thatcher stays out of jail

Sir Mark Thatcher was planning a swift exit from South Africa today after pleading guilty to involvement in a failed coup plot and agreeing to accept a suspended prison sentence and fine of about £300,000.

After months of virtual house arrest in Cape Town, the 51-year-old businessman was understood to be planning to join his wife Diane and children, Michael, 15, and Amanda, 11, in the United States, as soon as his passport is returned by South African police.

He appeared at Cape Town's High Court today where his plea was entered. A five-year suspended prison sentence and the fine were confirmed. His sister Carol told the Evening Standard: "This could have gone on and it was felt that it was better for him to plead guilty so he can get on with his life."

Thatcher's decision to admit helping to finance an attempt to depose the government in oil-rich Equatorial Guinea came after discussions with his mother, Baroness Thatcher, the former Conservative prime minister.

"She was there over Christmas and New Year," Carol said. "I don't know what was said. But you have to remember that she is a trained lawyer."

According to one of Sir Mark's friends, Baroness Thatcher and her son spent hours in "long and agonising" discussions about his case. She flew home to London last week and a spokesman said: "She is very relieved that matters have now been settled and the worry of these last few months is over."

Baroness Thatcher, 79, has suffered a number of minor strokes and has battled against frail health, but friends who saw her at a gathering in London recently said she was in "remarkably good shape".

The threat of a long jail sentence hanging over her only son had taken its toll, however. Thatcher was arrested at his £2 million home in Constantia, an expensive residential enclave outside Cape Town, last August.

It was alleged that he had put up £153,000 to provide a helicopter for mercenaries who were intercepted in Zimbabwe as they flew to Equatorial Guinea with a plan to overthrow the president, Teodoro Obiang. The mercenaries were led by Thatcher's close friend and

Cape Town neighbour, Old Etonian and former SAS officer, Simon Mann.

Mann, 51, is currently serving a jail sentence in Zimbabwe after admitting arms charges. Sir Mark's lawyers say he is only pleading guilty to " unwittingly" attempting to finance the coup plot.

"Mark had no idea that [the helicopter] would be used in a coup attempt," a source within his legal team said. "He became suspicious of the people he became involved with and he now believes he should have acted on those suspicions and taken appropriate action."

This version of events is not supported by evidence seen by the Evening Standard. A statement made to police by Crause Steyl, the South African pilot who flew the helicopter, makes it clear that Thatcher knew what was being planned.

Copies of Sir Mark's telephone records, also seen by the Standard, reveal that he had a number of conversations with key figures in the plot in the months before Mann and his 69 mercenaries flew to Zimbabwe. After their arrest, in March, and the unravelling of the plan Thatcher exchanged a flurry of telephone calls with the main authors of the coup attempt.

And, we can reveal, he came under enormous pressure when the plot collapsed. He received death threats from one of the mercenaries who was trying to persuade him to give money to help free the men jailed in Zimbabwe. At one point Sir Mark was told: "We know where your children go to school." Shortly after, his wife Diane took the children to Dallas. The evidence indicates that Thatcher hoped to make millions of dollars from his part in the scheme. Mann boasted that he wanted "ten million".

The money was to come from Equatorial Guinea's oil revenues, which are the third largest in Africa. The idea was that once President Obiang was overthrown - or assassinated, if necessary - he was to be replaced with Severo Moto, an exiled opposition leader.