A company director who saw an Egyptian billionaire accused of being a Mossad double agent fall to his death in London has spoken for the first time about his belief that it was murder.

Jozsef Repasi, from Budapest, the Hungarian capital, was interviewed by police investigating the death of Ashraf Marwan, the son-in-law of the late President Nasser.

After the fall, Mr Repasi told The Times that he saw men “of Middle Eastern appearance” staring down at Dr Marwan’s lifeless body from a balcony. The men then disappeared and reappeared on another balcony, he said.

Yesterday the police confirmed that there were men on the balcony but declined to say who they were or whether they had been interviewed.

Dr Marwan, 62, a businessman and former political and security adviser to President Sadat, died on June 27 after falling five floors from his suite of apartments in Carlton House Terrace in Central London.

He has been described by historians as the “most infamous spy in the Middle East”, who had worked closely with security agencies including MI6, the CIA and the KGB.

His death came after recent allegations over his role during the 1973 Yom Kippur War. The former head of Israeli military intelligence had claimed that Dr Marwan was a crucial spy who aided Israel. Others have said that he was an Egyptian double agent, feeding Israel misinformation with the knowledge of the Egyptian Government.

Police have described his death as unexplained and are exploring three possibilities: that he was murdered, that he jumped or that he fell accidentally.

Mr Repasi, 43, who had been a colleague of Dr Marwan for five months, said that he believed that he was probably murdered or was made to jump.

“I do not believe that he would have killed himself unless he was forced to,” he said. He said that he saw a body flash by his window, and looked up at a balcony from which Dr Marwan is believed to have fallen.

“I saw two men standing on a balcony. They were doing nothing, just looking down. Their calmness struck me as unusual. A lady was screaming in the garden. People were rushing around trying to help or call. But these two men were just standing there,” he said.

Dr Marwan died at about 1.40pm while 200 yards away, helicopters hovered overhead as the media focused on Tony Blair having driven from Downing Street to Buckingham Palace to resign as Prime Minister.

In an investigation that had already proved unusual, detectives had found that three crucial witnesses were fellow company directors of Dr Marwan, including Mr Repasi.

Board members of Ubichem plc were, at that time, holding a board meeting in the Institute of Directors building in Pall Mall, Central London, to discuss the possible sale of the company. Dr Marwan, its biggest shareholder, was expected to join them later.

The room they had hired was on the third floor only 15 yards away from, and looking on to, Dr Marwan’s £4.4 million apartment.

Mr Repasi said: “I was discussing the company with [a director]. And then someone said, ‘Look at what Dr Marwan is doing’.

“I turned left and saw him falling. He was already in the air when I saw him first. I then moved a metre to the window. I looked down towards where he must have landed but the view was hidden by bushes and trees,” he said.

It was then that Mr Repasi said he had looked up to see the two men, who were wearing dark clothes, staring down on a scene of pandemonium.

“I noticed the two gentlemen on the balcony,” he said. Mr Repasi added that another colleague also noticed the two men, who then disappeared and then reappeared.

Mr Repasi, a chemist, said that he had first met Dr Marwan in February when he had joined the board of the company, but had since met him on four occasions. He said that he was convinced that Dr Marwan did not kill himself.

“My private opinion is that he may not have been pushed but that he was forced somehow to jump by someone on the balcony or in the room, forced to commit suicide. I spoke to him two days before his death, and he was making plans. He was waiting for this meeting,” he said.

Mr Repasi said he was interviewed by a detective from the Metropolitan Police in his office in Budapest in September. He said that he would like to see photographs of Dr Marwan’s balcony from the room where the board meeting was held, so that he could try to identify the two men. “I would like to decide for myself whether these men were on Dr Marwan’s balcony,” he said.

Dr Marwan was alone in the study of his 15-room apartment at the time of his death, while a maid was working in another room. She heard nothing when he fell from the balcony.

He had been working on memoirs entitled October 1973 - What Happened, which he had almost completed, according to members of his family.

The police were informed that the only known copy of Dr Marwan’s memoirs had disappeared from his flat on the day of his death.

A source close to the investigation also said that his wife, Mona, had told police that her husband had warned her on three occasions that he might be murdered. His latest concerns came after an Israeli court ruled in early June that Major-General Eli Zeira, who headed Israeli military intelligence during the 1973 war, leaked Dr Marwan’s identity.

Israeli sources have claimed that Dr Marwan was recruited by Mossad in 1969 and in 1973 handed over files that showed Egypt’s plans to cross the Suez Canal.

However, Egyptian sources have said that Dr Marwan fed misinformation to the Israelis for years with the approval of President Sadat.

Dr Marwan moved to Britain after the President’s assassination in 1981.

A spokeswoman for the Metropolitan Police said that officers believe that they have identified the men on the balcony, but declined to comment further.

In mysterious circumstances

Ashraf Marwan is believed to have been the third Egyptian national with alleged ties to security services to die by falling out of a balcony over the past 33 years

— Suad Husni, 58, an Egyptian film star who reportedly maintained ties with Egyptian Intelligence, died in June 2001 after falling from her apartment balcony in Maida Vale, northwest London. Friends still argue that she was murdered, but it was decided in 2002 that she had committed suicide.

Husni was known as the Cinderella of Arabic cinema and one of the most influential actresses in Egypt. She was given a state funeral.

— Al-Laythi Nasif, the Republican Guard commander during President Sadat’s rule, died in 1974 amid rumours that he was writing an exposé of his Government. He and Husni fell to their deaths from the same block of flats.

— Egyptian commentators have seized on the cases as evidence that London is a dangerous place for their fellow citizens. A presenter of Cairo Today on al-Yawn television warned Egyptian businessmen “who have always believed that London is a safe house” that “the British capital seems to be no longer safe for Egyptians”.

— In another commentary in a daily newspaper, Khayri Ramadan wondered about “these damned balconies in Central London, on which only Egyptians, particularly controversial figures, stand and suddenly fly like a pair of socks”.

Times Recommends

• Rio Tinto four held as China prepares case
• Diplomats must keep heads down and trousers up
• When in Rome should one make like Berlusconi?