As a modern European — German by birth and British by choice — I am a first-hand beneficiary of Europe’s freedoms. A whole generation now takes for granted the chance to travel and work across Europe. These opportunities changed my life. When I came here in 1974 I did not need a work permit, I had the right of residence and I could go on to a British university.

After 30 years here I have not only succeeded in learning English, the original purpose of my visit, but I am now the MP for Birmingham Edgbaston. In 1939 the constituency was represented by Neville Chamberlain. Now it is represented by a woman born near Munich. To my children, the notion of Germany and Britain at war would seem sheer fantasy.

So nobody needs to convince me that Europe has been a force for good. That is why I want to make sure that there is a European Union that is effective and democratic.

When I was appointed by the House of Commons as one of its two representatives at the European convention charged with drawing up the new European constitution, I was enthusiastic. I did not — and do not — prejudge the outcome of the intergovernmental conference next weekend which is meant to conclude the drafting.

But I confess, after 16 months at the heart of the process — I was on the 13-strong presidium committee which drew up the draft document — I am concerned. I am not convinced the proposed constitution as it stands will meet the needs of a Europe of 25 countries. The government does not have to accept it. Enlargement will continue without it, and so will the EU.

Valéry Giscard d’Estaing was one of those who compared the EU convention to the US constitutional convention at Philadelphia in 1787. I’d rather have been in Philadelphia. The most frequent justifications for a written constitution were to make the treaties more understandable to European voters and to streamline decision-making after enlargement. I support both; but at 335 pages, the draft document is hardly handy for a coat pocket, one of the original aims.

From my experience inside the convention, it is clear that the real reason for the constitution is the political deepening of the union.

The convention’s monthly debates were confined to short inspirational speeches, it having decided early on that it would not take votes. Thousands of amendments flooded in, and commentators often remarked how difficult it was to see from the outside how decisions were reached on what was kept in and what discarded.

All I can say is that it was equally difficult from the inside. In the early months, the presidium members would meet in a small room in the Justus Lipsius building 15 minutes’ walk from the European parliament. Attendance was limited to the 13 members, the convention’s secretary-general Sir John Kerr, his deputy and the press officer. Kerr, a former Foreign Office permanent secretary, conducted the proceedings with the skill befitting someone described in John Major’s autobiography as “Machiavelli”. (When Kerr asks you the time, you wonder why me, why now?)

After the first six months, presidium meetings became more frequent and lengthier. On several occasions we retreated to the Val Duchess, a small palace used by the Belgian foreign minister. It was at a dinner there, the weekend before the public presentation, that the skeleton of the draft constitution was given to presidium members in sealed brown envelopes.

We were not allowed to take the documents away. Precisely who drafted the skeleton, and when, is still unclear to me, but I gather much of the work was done by Giscard and Kerr over the summer.

There was little time for informed discussion, and even less scope for changes. Large parts of the text passed through without detailed discussions.

In the final weeks, meetings became open-ended and some lasted into the early hours. Giscard and his deputies, Giuliano Amato and Jean-Luc Dehaene, were an effective trio. Amato came up with elegant compromises and Dehaene was the man to strike deals.