Under fire: Lebanese millionaire who seems to know everybody

It is a trail of black gold that stretches from the gilded mansions of Cape Town and London to the jails and oilfields of Africa. It is a plot ever more intriguing, its characters increasingly well known.

But one man finds himself facing questions that grow harder with each passing day. For Ely Calil, owner of a £12m Palladian mansion just off Chelsea's Kings Road, is a man under siege. The notoriously private Lebanese multimillionaire is accused of being at the centre of the plot to overthrow the president of Equatorial Guinea, a dirt-poor, oil-rich state on Africa's west coast.

Lawyers acting for the country's president, Teodoro Obiang Nguema, are seeking millions of pounds in compensation and costs from Mr Calil in a legal action due to be brought in London. The High Court writ, seen by The Independent, is issued in the name of President Obiang and the Republic of Equatorial Guinea. It names Mr Calil, along with two companies - Logo Limited and Systems Design Limited - and two other Britons, Greg Wales and Simon Mann. It also names the exiled leader Severo Moto.

The writ says the overthrow of the government of Equatorial Guinea was planned by acts illegal under English law "namely unlawful force and by unlawfully abducting and or injuring and or murdering" Mr Obiang.

It seeks damages to meet the costs of increasing security in the country and an injunction to prevent the alleged plot continuing. Court documents describe Mr Calil as an "ally" of Mr Moto, and allege that in March 2003 and again the following month Mr Calil asked Mr Mann while in London to meet Mr Moto. It is alleged that the three met in Madrid in April and that further "regular meetings" took place. It details more alleged meetings and payments leading up to the arrests in Africa in March.

Mr Obiang is bringing the case under the little-tested laws governing civil conspiracy - accusations Mr Calil's solicitor, the leading human rights lawyer Imran Khan, says have no substance. He plans to contest them vigorously.

Mr Calil is no stranger to controversy or, indeed, the legal process. He has been investigated over illegal payments allegedly made in connection with contracts between the French state-owned oil giant Elf-Aquitaine and the Nigerian government.

The Elf scandal spawned France's biggest ever corruption trial. Last year, the former chairman of Elf, Loik Le Floch-Prigent, who was appointed by President Mitterrand, was jailed for five years after an eight-year investigation into the siphoning off of some £200m before the company was privatised in 1994. Mr Calil was arrested in Paris in connection with the probe but released on appeal. The allegations are still under review by the French authorities.

Mr Calil has been rarely photographed over the last 30 years, and friends remain loyal and discreet. A former financial adviser to Lord Archer, Mr Calil is said to be part of the disgraced peer's inner coterie.

Mr Calil's world even drew in Peter Mandelson, the European Commissioner for Trade. The former Labour MP rented a luxury flat in Holland Park from Mr Calil after he lost his cabinet post in the wake of revelations of an undeclared home loan from fellow minister Geoffrey Robinson.

Last year, Mr Calil's eldest son, George, was arrested following the death of his girlfriend, the actress Laura Sadler, who played nurse Sandy Harper in the popular medical drama Holby City. Ms Sadler died while "watching the sunrise" after falling 40ft from the balcony of George Calil's Holland Park flat. The toxicology report at the inquest revealed large amounts of alcohol, derivatives of cocaine and a trace of diazepam in her body. Also an actor, George had played alongside her in Holby City. He was later released without charge.

It is thought much of Ely Calil's fortune was inherited from his father, George. The Khalils, as the family name was then spelt, had made their home in Turkey after leaving Lebanon. But they were forced to leave during Mustafa Kemal Ataturk's reforms.

Decamping to Nigeria, they set up the family's first oil mill in 1941, building a groundnut processing empire. George Khalil died in 1970 after amassing considerable person wealth, which he bequeathed to his sons Ely and Bernard. Ely, who is said to have inherited £20m on his father's death, ran the business from Mayfair in London, creating a profitable property portfolio and moving into high finance.

He married his first wife, the Tennessee tobacco heiress Frances Condon, at Farm Street Roman Catholic Church in Mayfair in 1972.

The couple divorced in 1985, and the following year Mr Calil married the Lebanese socialite Hayat Emma Morowa. This marriage also failed, and Mr Calil married his third wife, Renuka Jaine, in 1989.

CALIL'S CIRCLE

SIMON MANN

Former SAS officer who knows Ely Calil, Mark Thatcher, Nick du Toit, Gary Hersham, David Hart and Gianfranco Cicogna. Alleged role: masterminding Equatorial Guinea coup plot. Arrested in Zimbabwe with 70 alleged mercenaries, weapons and US$130,000 (£70,000). Says he was approached by friends of Mr Moto to stage the coup and sought funding from 12 British millionaires. Lawyers say confession was beaten out of him. He is charged with breaking arms regulations.

SEVERO MOTO

Madrid-based Equatorial Guinea opposition leader who knows Ely Calil, Simon Mann and Greg Wales. Alleged role: Mr Mann says he met Mr Moto in Spain in early 2003 and discussed installing him as leader of the country after an "uprising" to depose President Obiang. Said to be the prime instigator behind the coup. Mr Moto allegedly turned to mercenaries after Western countries rebuffed his request for help to restore democratic rule. He denies involvement.

GREG WALES

London businessman who knows Ely Calil, Mark Thatcher, Simon Mann and David Hart. Alleged role: he is named by the Equatorial Guinea government as one of a number of alleged coup plotters in a High Court writ. He claims Mann and Thatcher worked on deals involving mining, aircraft and fuel brokerage. His business interests include mine clearance in Somalia and consultancy. Mr Wales denies involvement in the coup.

LORD ARCHER

Disgraced peer who knows Ely Calil, Simon Mann and Mark Thatcher. Alleged role: legal documents and bank account details allegedly show payment from J H Archer to Mr Mann totalling $134,980 (£74,000) but Lord Archer denies knowledge of any coup plot. His friendship with Mr Calil goes back 30 years, but he denies a business relationship with him.

NICK DU TOIT

South African arms dealer who knows Simon Mann. Alleged role: on trial in Equatorial Guinea, where he was arrested with 14 other alleged conspirators for role in foiled coup. Has turned state witness. Told court that Thatcher helicopter purchase was "normal business deal". Was allegedly recruited by Mr Mann while training military personnel in Equatorial Guinea.

GARY HERSHAM

Mayfair estate agent who knows Ely Calil, Simon Mann and Mark Thatcher. Alleged role: none. Mr Mann says he travelled with him to west African state of Gabon in early 2003.

GIANFRANCO CICOGNA

South African-based telecoms tycoon who knows Simon Mann and Mark Thatcher. Alleged role: None. Says he discussed with Mr Mann investing $112,000 in a "project" in Equatorial Guinea.

DAVID HART

Millionaire businessman who knows Simon Mann, Mark Thatcher and Greg Wales. Alleged role: approached by Mr Mann for help from jail. The Old Etonian businessman is a trusted friend of the Thatcher family, having advised Baroness Thatcher during the miners' strike. Former special adviser to Michael Portillo.

MARK THATCHER

South African-based businessman who knows Ely Calil, Simon Mann, Lord Archer, Greg Wales and David Hart. Alleged role: bankrolling coup attempt. Alleged to have financed purchase of a military helicopter for coup plot. Approached by Mr Mann for help from jail. He says he is innocent of all charges.

PETER MANDELSON

EU commissioner and former British minister who rented a flat from Ely Calil for a year in 1999. Alleged role: none. President Obiang has accused a former British cabinet minister of involvement in the coup attempt but he has refused to name the person and there is no suggestion that it is Mr Mandelson.