All of them have said the amounts involved were immaterial.

No estimate was available for the smuggled volumes, but Cameroonian farmers and buyers said the amounts were significant.

But the Chinese official said the amounts should be put in perspective of how much rich governments have spent rescuing financial institutions.

Countrywide said the amounts represented reductions of 55.1 percent, 54 percent and 39.1 percent from 2007 levels.

But a source familiar with Warner Music's talks said the amounts it has been receiving from YouTube were "staggeringly low".

However, the Government Taskforce on Emergency Planning said the amounts of ash were small and there had been no deterioration of air quality.

Traders said the amounts involved were small but served to put a floor under the pound's fall at 100.2p.

Speaking at the committee meeting in Martinborough yesterday, Neems said the amounts were "worse than last year, but not worse than we expected".