'In my day people that had career paths like mine; people who had done real jobs in real life were not unusual. Now they're unheard of. You go into politics at 18 in short pants straight out of school and you've never done anything else. I think our politics is very much the poorer as a result.'

He arrives 10 minutes late at the Peers' Entrance - he was made a life peer in 2001 - to the Houses of Parliament and says he will have to rush off to vote at some point during the interview. As if on cue, the division bell rings, signalling eight minutes to go before voting begins. Asked if it is an interesting bill, Ashdown first waves his hand dismissively, then changes his mind, saying the bill is an important one on the funding of British political parties by foreign nationals.

Ashdown is a caricature of the no-nonsense military man. It is difficult to keep up as he strides ahead, curtly nodding to and dodging between less agile peers of the realm on the way to a quiet corner of the grandiose Royal Gallery.

He answers most questions in his slightly scratchy baritone in a practised, almost mechanical manner. It is only when explaining where he buried a few days' supply of food in 1968 - a time when Hong Kong authorities feared that the unrest in China could spill over the border - that he permits himself a chuckle. With no change to the deep creases in his forehead under a mop of white hair he recalls that time when, aged 27, he made the provisions for his family.

'I could almost draw a Long John Silver map,' he says. 'If you go up behind Repulse Bay and set a bearing of around south by east, about a mile and a half heading towards Lei Yue Mun, it's probably still there.'

In recent years Ashdown has probably been best known for his time as High Representative for Bosnia-Herzegovina, from 2002 to 2006. Appointed by the European Union, he was responsible for stabilising the nation following war with Serbia and implementing the civilian aspects of the Dayton Peace Agreement. In addition to endless rounds of discussions with high-ranking military and government personnel, Ashdown travelled into the countryside to meet people whose lives had been turned upside down by the conflict.

His decision to venture into the 'real world' stemmed from his time as leader of the Liberal Democrats. He disliked the 'clubbable' atmosphere at the House of Commons and chose instead to perform his MP duties from his constituency and hometown of Yeovil, or to travel Britain and learn how decisions in London affected average people.

He chronicled his experiences in 1994's Beyond Westminster, which he wrote at the family home in France.

Ashdown has largely managed to avoid controversy, although details of a brief extramarital affair did make it into the newspapers. But he says such stories usually arise from politicians' own failings and therefore deserve the publicity.

Ashdown visited the Balkans in the immediate wake of the disintegration of the former Yugoslavia, unaware of the role he would one day play in the region. He was referred to at the time as 'The Honourable Member for Sarejevo' because of his frequent questions about Bosnia in Parliament, which annoyed other MPs, including some in his party.

'It certainly obsessed me,' he says. 'Did it take over me? The tragedy and appalling failure of leadership and the complete failure of understanding and the pathetic excuses made by our leaders for not intervening reminded me of the bad old days of appeasement at the end of the 1930s. These certainly captured me and have a hold over me still.'

'I'm a Liberal. If you are an internationalist by attitude, then you are offended by international scandals and massacres. What I did in the Balkans was in the same tradition as [former British prime minister William] Gladstone and the [Bulgarian April Uprising] massacres, although Gladstone did it with greater power and sacrifice.'

That same liberalism drove him to petition the Thatcher government to give the 3.5 million ethnic Chinese in Hong Kong the right of abode in Britain post-1997, despite how deeply unpopular that plan was among voters.

'If that had happened, that huge amount of Hong Kong investment that went into Vancouver and the west coast of the United States would have come here,' he says.

'I still believe that if you look at the late 1980s-early 1990s Thatcher recession, that Hong Kong investment in Britain would have been immensely valuable. It would have softened it enormously.'

Born in 1941 in India, where his father was serving at army headquarters in New Delhi, Ashdown first visited Hong Kong near the end of 1966, when he was responsible for surveying the territory's beaches to find suitable evacuation points in the event of a mainland invasion. The following year he left a posting in Singapore to spend two-and-a-half years training as a Royal Naval interpreter in Putonghua at the Joint Services Chinese Language School.

Despite their political differences he remains a friend and supporter of former governor Chris Patten, who was EU commissioner when Ashdown was High Representative.

Asked if he would have liked to have been Hong Kong's last governor, Ashdown says: 'I would have preferred to have been High Representative of Bosnia and Herzegovina. But I love Hong Kong and I think Chris did a very interesting, very difficult and very tough job extremely well and he did it with great courage. I have a very high regard for him; he helped me a lot in Bosnia. He's the best prime minister we never had.

'He had great courage and enabled us to leave Hong Kong with some pride. He managed to ensure that the last page of colonialism was written with some dignity. It's a very great achievement and I think what he left behind has in large measure endured.'

Ashdown is the author of several political books and diaries, but his autobiography came only at his wife's behest after he threatened to learn how to cook.

With such an eventful life it might seem difficult for Ashdown to isolate one success as the pinnacle of his career, but, he says, one event stands out: winning the parliamentary seat for Yeovil on June 9, 1983.

'If someone said I could have one line on my tombstone, it would be 'Member of Parliament for Yeovil'. And remember this isn't a political book. If you want to know how much I wanted to be prime minister, you'll have to read the diaries. This is a book deliberately written to treat my political period as just another part of a long pattern of adventures.

'Of all the privileges I've ever had, representing my community in Parliament for nearly two decades would be the greatest. Next would be leading my party and if you lead your party, do you want to be prime minister? Why else would you be leading your party if you didn't?'

Writer's notes

Name: Jeremy John Durham 'Paddy' Ashdown

Age: 68

Born: New Delhi, India

Lives: Yeovil, Somerset, and Irancy, Burgundy, France

Family: wife Jane, children Simon and Katherine

Genre: political

Latest book: A Fortunate Life (autobiography)

Other works: Swords and Ploughshares: Building Peace in the 21st Century (2007), The Ashdown Diaries: 1988-1997 (2000), Beyond Westminster: Finding Hope in Britain (1994), Combat Frogmen: Military Diving from the Nineteenth Century to the Present Day (1989)

Other jobs: Royal Marine, Special Boat Service operative, diplomat, spy (while admitting he worked for British intelligence he has never confirmed it was for MI6), manager of a sheepskin apparel company, youth worker

What the papers say about A Fortunate Life:

'The man revealed here is that rarity - a politician not terribly interested in power - which makes this book very likeable and rather frustrating.' The Guardian

'[He] has a terrific tale to tell, and he tells it well.' The Daily Telegraph