And city shall speak unto city

CITIES will replace countries as the basic units of international power in the next century, according to a forecasting think-tank. At their heads, a new breed of civic mayor will stride the globe and, as the colossi of the new millennium, they are likely to replace the state diplomats of the 20th century.

The predictions come from the Henley Centre, which has outlined the crucial economic and cultural role to be played by the few, elite cities that manage to distinguish themselves as world-class.

Moscow, Tokyo, Mexico City, New York and London are all leading contenders in a race to win the business influence that will bring political power. Transport and infrastructure will have a large part in deciding who makes the grade, but cultural and historical resonances are also likely to weigh heavily.

"What is vital is that people working in other countries would be happy to go and live there," said Dr Michelle Harrison, who edited the Henley Centre's 1998 "Planning for Local Change" programme.

The number of international conglomerates that have their head offices in a particular city is a useful indicator of worldwide prominence, but the right combination of social attributes is essential.

"Our definition of a world city is a fairly loose one," explained Dr Harrison. "Some people would say they are going to be the biggest conurbations, but that is not always the case. An international profile is crucial. For example, look at the expansion of Prague in recent years."

The trend may eventually lead to a Europe that resembles late medieval Italy, where the great city states such as Florence, Bologna and Venice vied for trade and diplomatic sway. The ancient Greek city state or polis also operated in this way, with surrounding territory falling under the influence of its nearest urban centre.

Many of the larger Continental cities function a little like this now, but not those in centralist Britain. "Strong cities never went off the agenda in Europe," said Dr Harrison, "partly because in recent years it has helped them to gain European funding."

It is generally agreed that Britain has only one place that currently qualifies as a world city and that is London - but Edinburgh, Cardiff and Glasgow are all seen as being on the cusp of global stardom.

"Some cities will grab this opportunity," said Dr Harrison, citing Liverpool and Glasgow as examples of cities that are turning themselves around. "Our work shows, however, that certain localities can easily get themselves into vicious circles of decline, while others thrive on their own growth.

"The city has really got to deliver, although image is very important. They may have pockets of social exclusion, but they will need to solve their problems for business reasons - a high crime rate will deter investment."

Michael Gwilliam, the director of Britain's Civic Trust, is convinced that citizenship will become more and more important.

"It is a more constructive feeling than patriotism, which can be so easily misused. Cities are more robust, because they are about their citizens' whole lives," he said.

A thriving city such as those in medieval Italy, he pointed out, can be fantastically productive. "They become engines of invention and they are very creative in a way that a country can't ever be."