Ministers have welcomed a weekend poll that suggested the EU constitution referendum could be a closer battle than previously thought.

A ICM poll for the Sunday Telegraph put support for a yes vote on 39 per cent, fractionally behind the no camp's 41 per cent.

The result is closer than previous polls have predicted, but it was the first time the actual referendum question had been put to the public.

Europe minister Denis MacShane said that as people "learn the facts" about the constitution they back British engagement with Europe.