A written answer in the House of Commons yesterday:
Mr. Hayes: To ask the Prime Minister on which occasions in the last 12 months he has met representatives of campaign bodies and think tanks advocating closer EU integration. 
The Prime Minister: My officials and I have meetings with a wide range of organisations and individuals on a range of subjects. Information relating to internal meetings, discussion and advice is not disclosed as to do so could harm the frankness and candour of internal discussion.
It can’t be often, can it? And the meetings he has had have hardly had much visible effect. Of all the countries leading the debate about the future of Europe, Britain is simply hanging back to wait and see what might happen. Blair (and Brown) have the overriding priority of avoiding a referendum on the constitutional treaty; subject to that, almost anything goes.
It’s in France, in the presidential race between Nicolas Sarkozy and Ségolène Royal, that the major decision about the future of the constitution will be taken. Britain has chosen to be on the margins. Some of my continental friends think that’s a good thing.