Sir Peter Marshall was Commonwealth Deputy Secretary-General 1983-88 and UK Permanent Representative to the UN in Geneva 1979-83.

One frequently hears it said that there can be no “pre-negotiation” before the UK triggers Article 50.  This is misleading.

The second paragraph of the article specifies that “in the light of the guidelines provided by the European Council,   the Union shall negotiate and conclude an agreement with [the withdrawing] state, setting out the arrangements for its withdrawal, taking account of the framework for its future relationship with the Union” (my italics).

Much as some might like to do so, Brussels enthusiasts cannot plausibly maintain that construction of the framework has to be part of the negotiations: were that the intention, the words “taking account of” would have been replaced by “including”.  Nor can the framework form part of “the guidelines provided by the European Council” (to quote another part of the article).  Again, were that the intention, the point would have been made specific in that context.

As it is, the article is specific in precisely the opposite direction.  Paragraph Four stipulates – naturally enough – that the withdrawing state shall not participate when the European Council draws up the guidelines for the negotiations, nor in the subsequent discussions in the Council of Ministers.  However, a framework for our future relationship with the EU cannot be drawn up unilaterally without our participation.  We have to be involved.

The framework has therefore to pre-exist the initiation of the procedure envisaged in the second paragraph of Article 50.

It may be argued that this line of thought is of little practical importance, since what really matters is the actual negotiation and conclusion of the agreement and the consent of the European Parliament.  The requirement,  moreover, is only to ”take account of” the framework, not to be wholly subject to it.

This argument is unsustainable for two reasons.  First, the framework for the UK’s future relationship with the EU will have to address not only those matters in which the Union has competence, but also every other aspect of our relations with the other 27 other member states.  That is what we mean when we say we are leaving the EU, but not turning our back on Europe.  The negotiations cannot disregard the parameters of the framework.

Second, Brexit is a matter of worldwide concern – as will be the precise basis on which Article 50 is triggered, when the time comes.  The pressure for the text of the framework to be made public, as soon as it is agreed, will rightly be very strong.  World opinion will likewise expect the guidelines to be respected once the Article 50 procedure is initiated.

The appropriate course would be for the UK and France, acting on behalf of the EU, to transmit the text to the United Nations, and ask that it be circulated as a UN document.

It may also be argued that the EU will want as innocuous a framework as possible, so as to give the Commission the greatest possible freedom of manoeuvre in the negotiations.  Experience suggests that such freedom is unlikely to be exercised with benevolent impartiality.  Hostility at EU headquarters to the very idea of UK withdrawal may be natural enough.  Indeed, there is an element almost of disdain in the wording of Article 50, more in evidence in the French text than in the English.  The withdrawing state is implicitly regarded as something of a delinquent, meriting only peremptory treatment.

Again, the argument carries no weight.  The framework should properly include reference to the international obligations shared by all parties, including the other 27 member states, and those acting on their behalf.  In this connection, it is natural to think of the aims and objectives of the iconic Preamble to the UN Charter and the major texts adopted during 2015, the United Nations’ 70th anniversary year.

Those obligations should be fully reflected in the agreement.  They include not seeking revenge on another member state for legitimately exercising of its sovereign democratic rights.

The agreement, when concluded, will have to be registered with the United Nations in accordance with the provisions of Chapter XVI of the Charter.  Responsibility for the interpretation of the agreement would rest with the International Court of Justice,  rather than to the ECJ.  Furthermore, the framework could usefully include reference to the Union’s own recognition of its international obligations, as set forth in EU general declarations,  notably those of Nice (2000),  Laeken (2001) and Berlin (2007).

Virtually without exception, the leaders of other democratic countries wanted – indeed urged – us to remain in the EU,  for fear of the unpredictable consequences of our leaving   But they have in general accepted the verdict of the British people, as has our Government.

They now expect that the British Government will do everything in its power to reassure world opinion that we remain as determined as ever to play our full constructive part in the management of world affairs,  and that, within that general commitment, we shall seek as mutually favourable a deal as possible with our European partners.

A  co-operative,  imaginative and reassuring approach to leaving the EU was outlined by the Prime Minister in her speeches at last week’s Conservative Party Conference (as supplemented by a number of other statements,  in particular the Chancellor’s speech to the conference, and the International Trade Secretary’s address in Manchester Town Hall shortly before it began).

This approach is as sound a basis for starting to build the framework for the negotiations as world opinion could reasonably desire.  Our EU partners can surely find little in it to which they could take reasonable exception.

Unhappily, there is much in the attitude already adopted in some EU quarters which world opinion would regard as falling short of the ideal.   A prime cause of concern is the conviction, seemingly held among Brussels diehards,  that the UK must not be seem to gain from its departure, lest “contagion” spread among other EU member states.

Beggar-my-neighbour tactics are no proper basis for building a framework for anyone’s future relationship with the EU,  or with anyone else.  We must all – repeat all – play a Positive-Sum Game, not a Zero-Sum Game.