Europe - Why Cameron's speech is proving so hard to write

It is a year since the prime minister found himself isolated in Europe at a summit determining the EU's future. It is six months since he signalled that he might be open to a referendum on Britain's relationship with the Europe. Yet David Cameron has still to fix a date let alone finalise the text of a long promised speech spelling out his European policy.

I understand the PM held a meeting with the foreign secretary and the chancellor on Monday to agree the content of a speech which will see him walking a political and diplomatic tightrope.

Another meeting may follow on Tuesday. David Cameron's aim is to satisfy those in his own party, as well as those who have defected to UKIP, that they will get the meaningful vote on Europe they have long craved for while reassuring the leaders of both other countries and multi-national companies that this will not represent the first step on a road taking Britain out of the EU.

Senior Tories have little doubt about what the core message will be - a promise to hold a referendum after negotiations in which Britain would attempt to secure a new looser relationship with the EU. In other words, not an IN/OUT vote on Britain's EU membership on current terms but on new terms when/if they can be agreed.

One reason for the agonising over this speech has been what one source calls "getting the diplomacy right" ie ensuring that potential allies in Europe - the Germans, Dutch and the Swedes who have, so far, backed Britain's call for a freeze in the EU Budget - are clear that Mr Cameron is not capitulating to those who want Britain out of Europe.

He needs them in future negotiations not just on the budget but also on reforms of EU banking rules.

Another problem is what some ministers call "the Honda problem" - the risk that multinational companies put further investment in Britain on hold while they wait to see if the country will stay in or get out of Europe. Many voters see the EU as the cause of our economic problems. It would be politically disastrous for the Conservatives if their approach to the EU seems to make our economic prospects worse.

There is diplomacy to be done at home as well as abroad with Tory Eurosceptics who will question the worth of a referendum promise without a date attached and who will demand to know what the prime minister would do if he cannot get his way in negotiations.

The former Defence Secretary Liam Fox has been clear about this - he would be prepared to see Britain get out.

What's more there is the question of how this speech will affect the coalition. Most expect a referendum to be a Tory manifesto promise enacted some years hence.

However, it is possible that Germany's Chancellor Merkel - if she is re-elected next year - might push for treaty change before the next General Election.

No wonder Mr Cameron told a journalists' lunch on Monday he was trying to balance "what I think is right for the country, what I think is politically deliverable and what is deliverable diplomatically".

To the surprise of his aides he went on to explain that his was "a tantric approach to policy-making - it will be even better when it does eventually come".

He hastily added "that wasn't in the script." Many are getting impatient to discover what exactly is.