THERE are many important issues to resolve before flying off to Brussels with the Prime Minister tonight to represent Britain at what is an extremely important summit of European Union governments.

But perhaps the hardest decision I have to make is: how many shirts should I pack?

For the truth is that no one quite knows for how long this conference will go on.

We could be back on Saturday afternoon -- in which case I will need just two clean shirts -- or it could be Sunday or Monday.. but if discussions get tricky, we could be still talking well into next week. That will have profound implications, not least for my wardrobe.

It would be fair to say that European summits have not always had finest reputation. Negotiations take place behind closed doors to allow national representatives to discuss issues freely without the glare of the media pressure. But in doing so these meetings can confirm some pretty strong prejudices.

No doubt, for those who want to see Britain leave the European Union, summits represent the time when national leaders secretly collude to plot the next step in the creation of a superstate. On the other hand, the "starry-eyed" federalists who want Britain submerged into a new United States of Europe, see the occasion as one when national leaders promoting selfish national interest subvert the proper European ideal.

The truth is a little more simple, although perhaps more profound. While I wouldn't argue that summits are always the most enjoyable parts of being Foreign Secretary, they are the expression of how far Europe has come. For hundreds of years our continent knew little but conflict, culminating in the terrible carnage of two world wars last century. I think most would agree that EU summits are a better way of resolving disputes in Europe.

The meeting itself will be dominated by discussions about a new Constitutional Treaty which will signal big reforms in the way the EU works. I believe change in Europe is well overdue. After all, public confidence in Europe is not at an all-time high right now -- and we have to make the Union more effective in delivering on trade, cross-border crime, illegal immigration and the environment, issues which people in East Lancashire and elsewhere know cannot be tackled by individual countries acting alone.

And there is a further reason for change too. As well as the 15 existing EU nations, there will be 10 extra countries around the table in Brussels which are set to join formally next May but are taking a full part in these treaty discussions. But European institutions which were set up to work for the old Common Market of six or nine members will not work effectively with 25 or more.

The expansion of the Union is a wonderful thing. The single market for British companies will grow to more than 440 million people -- larger than the US and Japan put together. That can only be good news for British jobs and British trade - not least for East Lancs.

And it will be the final end to the terrible East-West division of Europe. So it's an important weekend, and we will be working very hard to reach agreement. But not at any cost. Britain is stronger, more secure and more prosperous as a result of our membership of the EU. Yet there are issues, such as tax and foreign policy, which must remain the preserve of nation states.

It is a close call to make but I hope we get our Treaty - and, fingers crossed, I'll be able to return to Britain with one or two shirts left untouched. Now that would be a bonus.