The most remarkable characteristic of the newt is its ability to regenerate itself. If the newt, say, loses a limb, an eye, intestine or jaw, it simply grows another. In effect, the newt can grow itself anew.

This is what Ken Livingstone, Britain’s best-known newt-fancier, has achieved, in the process evolving an entirely new political species that will remain a permanent feature of the political landscape: the Mayor of London, the first directly elected mayor in Britain, and the politician with the largest individual democratic mandate in the country.

When the idea of a London mayor was first mooted, more than ten years ago, some predicted that this odd hybrid creature, imported from the US, would not survive here for long. But survive it has. Whatever one may think of Mr Livingstone’s success or failure, the office is here to stay.

Its creation was a bold constitutional experiment, and something of a gamble. The tradition of strong city government has not thrived in Britain as in other parts of the world, for ours has usually been a monarchical-type system, ruling from the top down and the centre out.

For most of the past century, London, like most British cities, was governed through a mixture of councils and committees, with the office of mayor a ceremonial accompaniment. Dick Whittington may have aspired to be Lord Mayor of London, but most ambitious politicians aimed higher.

The London City Council gave way to the Greater London Council in 1965. The epic battle between Margaret Thatcher and Mr Livingstone, arrayed on either side of the Thames in Westminster and County Hall, ended with the abolition of the GLC in 1986. For the next 14 years, the running of schools, housing and social services was left to the 33 London boroughs, with a minister for London and a Cabinet committee, but no democratic coordinating body, and no single, powerful voice to speak for London.

A White Paper in 1998 outlined the problem: “On the one hand [London] is one of the most competitive [cities] in Europe, a beacon of enterprise, creativity and culture. Yet on the other, it is beset with problems of congestion, pollution and social deprivation . . . it is a city fill of energy, but where the big issues do not get sorted out.”

Inspiration for the new mayoral post was drawn directly from the big city mayors of the US, and New York’s Republican Mayor, Rudolph Giuliani, in particular. Since 1994, “Hizzoner” Giuliani had ruled New York with a combination of grit and showbusiness that proved highly effective in reducing crime, tackling welfare abuse and bolstering civic pride.

The blueprint for the new office of London mayor was essentially a presidential system with power concentrated in the hands of one man. The mayor would have wideranging powers over transport, planning, the police, fire services, cultural strategy, economic development and the environment.

The boroughs would continue to control education or housing, but the mayoral election of 2000 created the most powerful city official in British history, replacing the traditional pattern of committee-dominated local councils and ceremonial mayors with a single, highly visible leader.

“This is a post with teeth,” declared Tony Blair, envisaging that it might attract a different sort of politician, perhaps a senior businessman. “There is no question that the mayor has the power to change things for the better.”

In some respects, however, the new mayor’s power was strictly limited. A small, 25-strong elected assembly would hold him to account, scrutinise official documents and help to set the budget (although a two-thirds majority is needed to draw up an alternative budget). The budget itself, at less than £4 billion – much of it earmarked already – meant that the London mayoralty was hardly paved with gold.

The mayor’s powers are not so much statutory as electoral. With a direct mandate from about five million London voters, the mayor, in the words of another White Paper, wields “exceptional influence”, not just in London, but nationally and globally. His executive powers are exercised, not through neutral managers, but via a group of partisan senior assistants, his own “team”, which remains in power only as long where he had left off at the old GLC. On election night he declared: “Now, before I was so rudely interrupted 14 years ago . . .”

He did nothing of the sort. One of his first acts was to visit Mr Giuliani at Gracie Mansion, where the two mayors ate bagels and scrambled eggs. In the past Mr Livingstone had accused Mr Giuliani of “paramilitary policing” and playing “a divisive role”. He emerged declaring that Mr Giuliani was “the standard by which all mayors will be judged in the future”. The newt had grown a new limb.

Mr Livingstone could never hope to replicate Mr Giuliani’s muscle as a big city boss, but by careful deployment of the limited powers at his disposal the job of mayor was established swiftly, partly because of the way the office had been set up, and partly because of the personality of the man occupying it.

Far from dusting off the ideological cudgels of the GLC, his approach was pragmatic. American experts were brought in to run the Tube, links were cultivated with big business and property developers. “Red” Ken, now “Citizen” Ken, was even seen singing Abide with Me at the Queen Mother’s funeral. He cut deals, negotiated, and used influence to ensure that his restricted powers extended beyond the ceremonial.

The congestion charge, like it or not, established that the new Mayor of London could achieve innovations that the old system of committees and councilmen would never have had the clout or courage to pull off. It seems highly unlikely that the Olympics would be coming to London without the mayor as chief booster and figurehead. The attacks of July 7, coming so swiftly after the Olympics announcement, enabled Mr Livingstone to cement his role as the city’s preeminent spokesman.

Like Mr Giuliani, he has felt licensed to comment and lecture on every aspect of city life, from planting trees to feeding pigeons and flushing the lavatory, thus cementing his role as the personification of what he has termed “London nationalism”.

The London Assembly has hardly impeded him. Running what some have referred to as a “Kenocracy”, Mr Livingstone rules through a small and trusted cabal of advisers, a far cry from the bloated GLC with its 21,000 employees. “The reason we can do things quickly is we don’t have Sir Humphreys and civil servants,” he said recently.

Yet at one point in his regime, Mr Livingstone employed 27 press officers, reflecting another aspect of the new job: its very high profile. Long before Mr Livingstone was elected, George Brooker, the veteran council leader of Barking and Dagenham, predicted that the post would attract “some egotistic bastard”.

As a one-man band, making noise is part of the job description, in an office requiring negotiating nous, media talent, and the ability to appeal simultaneously to sink estates and the Square Mile. Again, the recipe was American: Mr Giuliani was extrovert, outspoken, brash, and wildly successful; his predecessor, David Dinkins, was charming, clever, understated and regarded widely as a crashing failure.

Illtyd Harrington, Mr Livingstone’s former deputy at the GLC, once described him as “pure South London music hall”. After eight years in power Mr Livingstone was desperate to retain the part; but whoever ends up centre-stage at City Hall, the role of mayor he has helped to create will run and run.

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