David Cameron was first in to see the European Council President Herman Van Rompuy this morning in what will be a series of “confessional”meetings – they’re listed in order here.

In the European Council document they each have 15 minutes next to the government leader’s name (with the exception of 30 minutes with Cyprus – current holders of the EU presidency).

But the chances of getting a meeting like this done in 15 minutes are remote – as David Cameron proved with his 35 minute meeting.

That probably means that the 27 meetings will drag on later than planned and the tantalising “cold dinner” the leaders have been told will start at 8.30pm could well come later.

At that dinner, Herman Van Rompuy will speak to the budget proposal he’s been telling leaders about in the days coming up to this summit and maybe sketch some first thoughts based on today’s conversations about how it could be changed to get everyone on board.

In his chat with Van Rompuy this morning, David Cameron wasn’t shown any new proposals but was probed on whether he could accept the current proposals for a budget of 940bn euros.

He said that wasn’t acceptable and said the commission should look for more cuts and start with those budgets that are growing considerably – like the European Commission President Barroso’s pet project, Connecting Europe , currently projected to treble in size.

The prime minister mentioned again the need to cut back administration costs and made several other suggestions which we may hear more about as the day drags on.

Quite what the PM and his counterparts are going to do in the down-time isn’t clear. There’s only so much “Angry Birds” you can play. An aide said he’d brought a “box” with him and I wondered if he meant a “boxed set” – it was a ministerial red box. The weather’s amazing in Brussels, cloudless and bright, so he might take a walk.

What’s his bottom line? His dream would be a cut or some budget figure he could plausibly sell as a cut. Recipient countries don’t want to give him that. He can’t support an increase if he wants to escape from his own backbenchers with his political life. So his hopes rest on getting an overall budget that can be described as a “freeze”.

But what’s the number for that? The one that gets quoted is the Treasury’s estimate of a real terms freeze from 2011 levels: 886bn euros. But No. 10 has been careful not to put an exact figure on what constitutes a “freeze” – “we have a few numbers in mind,” one aide said, suggesting there’s some flexilibity though it’s phenomenally little for a 27 country negotiation.

The latest Van Rompuy proposals are for a 940bn euro budget – closer, but not acceptable, David Cameron’s team says. The gap is in the order of £50bn, and that’s over seven years of spending.

You might think it shouldn’t be beyond the wit of able officials to scrape money out of some of the growing budgets and if necessary make some side deals to keep recipient countries happy. But David Cameron’s not the only one here with domestic politics to deal with and political rhetoric to live up to.

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