Don't believe his son Saif, the Gaddafi era is definitely over

In Libya's embassy building in Knightsbridge yesterday morning the excitement was unmistakeable. In a darkened reception room to the left of the entrance hall a suited staff member was holding a morning newspaper and watching a small TV screen intently.

"Everyone is watching the news," said the smiling guard who lead us up the stairs to the ambassador's office, where - right on cue - Mahmud Nacua was watching the news on a big screen next to his desk, also smiling.

The embassy's staff had been taking calls from London's Libyans all morning, Nacua told us.

"They are very happy for what has been done by the fighters. They feel that the era of Gaddafi is over. His last page was last night." An hour before I arrived in the building, Nacua had addressed the camera crews on steps outside, telling them, "Today we start to rebuild Libya" and talked about looking forward to the "promised Libya".

The rebels' first envoy in the UK had spent Sunday night with his family at home in Harrow, watching as the unrest that started in his hometown of Zentan in February came to what seemed like a spectacular, victorious conclusion on the streets of Tripoli. After our interview around a table in his office was concluded, a man in chinos and a dark shirt entered the room and embraced Nacua, the two men laughing at each other and speaking animatedly in Arabic.

When I called back this morning, Nacua admitted that the atmosphere was nervous. But with news outlets questioning yesterday's assumption that Tripoli was in rebel control, the ambassador was in bullish mood, suggesting that reports of a Gaddafi fightback were "information mistakes".

"It is not true," he told me, referring to reports that Gaddafi had regained control.

"Politically the Gaddafi era has ended. There is some fighting in isolated areas but it will be finished in a few days or a few weeks. But politically I can confirm that Gaddafi and his regime is ended."

Asked about Saif Gaddafi's claim last night that his father's regime was running Tripoli again, Nacua said: "I can confirm that the rebels control 90 per cent of Tripoli and most of Libya's cities. My sources tell me that many of Gaddafi's supporters among the high ranks have defected and many have asked the NTC to give them safe haven and have joined the revolution."

If events prove him right, it won't be the first time. In a short interview two days before, Nacua had predicted that events in Libya would move more quickly than British sources realised. Not without cause, he tells me. "I knew because I have contact with some people who are in Zintan, in Tripoli and in Benghazi. And they were very confident about what they were doing. They knew from the arrested soldiers and mercenaries that the morale of Gaddafi's supporters was very weak."

In a rare article in English, months before Nacua's career as a writer and a journalist was transformed by his appointment to the embassy, the dissident of 33 years had written that "Libyans utterly reject any foreign intervention, even for their defence and protection". That was before Gaddafi turned his guns on civilians, and with the dictator now in hiding, Nacua believes his country is heavily in Nato's debt.

"The fighters could not reach Tripoli last night without Nato. I always said Nato has laid a big role in this crisis by destroying a lot of Gaddafi's machines."

Few feel the significance of ongoing events like Nacua. The 33 years he has spent away from Libya have claimed the lives of several friends and two family members, the latter killed in one of the most notorious episodes of the Gaddafi era.

"Two of my family were killed in the massacre of Abu Salim," he relates mournfully, referring to the murder of more than a thousand prisoners - including his cousin and his nephew - at the high-security Abu Salim prison, which was reportedly liberated on Saturday night.

Having come to London to study in English in 1978, Nacua never dared return and the emergence of the Revolutionary Committees in 1980 turned him into an activist. "I and some of my friends decided to have a new organisation of opposition called the National Front for the Salvation of Libya. I was one of the founders and one of the leaders," he says. Did he know his life was threatened in Libya? "Of course."

After time spent in Morocco, Iraq, Egypt and Sudan, Nacua settled in London in 1988 and started a family, writing for the Arabic press and penning books about Libyan political history and his liberal take on Islam.

For some of his friends, Gaddafi's henchmen were impossible to escape. "They liquidated many opponents, most of them my friends, like Muhamed Mustafa Ramdan [a BBC journalist killed in 1980]. It happened in London. It happened in Rome. It happened in Beirut."

Returning home was a prospect Nacua and his fellow dissidents wrote off years ago. "I had a dream in the past and I thought that dream was very far away. I didn't think I would live to see it happen," he says, but three decades after he arrived in London as a 41-year-old student, catching a flight to Tripoli with his three sons - who have never been to Libya - could be just a few weeks away.

"It will be a very significant day for me, my family and my friends. I will see my country, my birthplace, after 33 years away."

Unsurprisingly, the ambassador doesn't share concerns about the elusive men who could take the reins of power in Libya or the instability that some predict will hamper their efforts.

"All of them believe in democracy, and parliament and elections. But I think their first step is to have a technocratic government now as a transitional government, to look after the services of the people and their security. It will not be a political government, and after about eight months will start the permanent institutions."

The accidental ambassador hopes the a new regime in Tripoli will help to heal the open wounds left by the Gaddafi era. He is hopeful that Yvonne Fletcher's killers might finally be brought to justice, and offers to co-operate in any way he can. That might include handing over some of the piles of unexamined documents lying in the Knightsbridge embassy's cellar, left over from the building's previous occupants. "Maybe if the file is reopened we will know a lot of information about that."