Economists are worried that the trend is so strong now that those coming to the UK to work may never return, which could have a negative impact on Spain.

In the short term, Edward Hugh says it's not a problem, because it brings down the unemployment level somewhat. However, because many of the Spaniards arriving here - and in other European cities like Berlin - are very well qualified, it could herald a loss of valuable human capital in the medium or long term.

About six million people arrived in Spain in the heady days of the construction boom in the first decade of the century, he explains, and those same people are now also leaving - the country lost 400,000 people last year.

On the political level, Hugh says Spanish politicians have missed a trick by paying too much attention to the ageing population - most voters are now over 50 - rather than to the younger generations.

"There's a lot of disenchantment among young people. Government has maintained the level of pensions as a priority, when really they should have paid much more attention to the future of Spain's young people. Unfortunately politics and economic necessity don't meet up very easily here."

The birth rate has been dropping steadily, so these young emigrants are "very precious", he says.

If the young people were just going out to get an experience in another country, it would be a different story, but Hugh says that they may settle and stay in those other countries.

"The big fear is that this temporary loss could become a permanent one, because Spain could get stuck in a stagnation like what we've seen in Japan, with very low growth rates, and not a lot of attrction for young people ot stay here. Spain is also at a high level of risk of deflation, which makes the Japan worry even closer to home."

Asked about the current government's policies, he says the problem is that the government is more concerned about winning next year's elections by measures such as trying to lower taxes, rather than tackling the tougher structural problems in the economy.