President Sarkozy of France embarrassed Gordon Brown yesterday, heaping praise on his “courage and loyalty” for ratifying the EU treaty without a referendum.

The president said that every other European leader was grateful to Mr Brown for not blocking the replacement to the EU constitution.

In return the Prime Minister signed Britain up to moves to create common EU immigration standards and cooperate on defence and nuclear policy.

At the conclusion of yesterday’s France-UK summit, the French president vowed to continue his charm offensive designed to draw Britain into deeper engagement in the EU.

“It is not simply a matter of a one-night stand. I believe that we can go in to next-day breakfast as well,” Mr Sarkozy said at a joint press conference with Mr Brown.

He said that every EU leader had reason to be grateful for Mr Brown’s “courage and loyalty” in ensuring that the treaty, which replaced the failed EU constitution, would be ratified in the UK. Mr Sarkozy repeated his call for Britain to play a fuller role in the EU rather than “being on the sidelines”. “We need the British to get Europe moving,” he said, hinting that he had rebuked David Cameron for his pledge to put the Lisbon Treaty to a vote during his private meeting with the Opposition leader.

For his part Mr Brown upgraded to formidable the entente that Mr Sarkozy had previously improved from cordiale to amicale. He said: “We believe that, working together, France and Britain can be an even greater force for good so, if you like, this will be the entente formidable.”

A 36-page communiqué agreed to deepen cooperation on issues including the reform of international financial regulations and institutions, defence and immigration. New arrangements were made to “combat nuclear terrorism” by screening cross-Channel traffic and the creation of a British civilian rapid reaction force to help to stabilise failing states. It was the leaders’ agreement to “take forward a new migration pact under the French presidency of the EU” that is likely to prove the most controversial, however. French ministers have said they want a “common definition of the right of asylum” and have backed European Commission proposals that could see asylum seekers shared between EU states.

Ministers sought to emphasise the measures that Britain and France were taking to deter illegal migrants, saying they had agreed to reinforce fences around the port at Calais, three weeks after a loophole was exposed. Illegal immigrants have been able to sneak aboard lorries in Calais because of inadequate fencing.

The two countries would also carry out a joint security audit and look at creating a fast-track system to introduce lighter controls on some goods vehicles, a statement from the Home Office said.

Ministers also agreed to cooperate to prevent any new Sangatte-type refugee centre developing at Calais or elsewhere on the Channel coast.

As expected Britain and France also agreed to harmonise the regulation of nuclear plants and work together to develop long-term waste facilities. The latter issue became more urgent yesterday with the publication of an official analysis giving warning that waste costs could prove prohibitively expensive for would-be investors.

Mr Brown said they had agreed a common approach to the problems in Afghanistan, Burma and Darfur, as well as the issue of nuclear proliferation. Mr Brown announced a joint British-Franco initiative to bring education to 16 million children in Africa.

Although both leaders called for restraint and dialogue in resolving the crisis in Tibet, Mr Sarkozy repeated his threat to boycott the opening ceremony of the Beijing Games.

“Depending on how the situation is looking at the time, I reserve the right to say whether I will attend the opening ceremony,” he said.

In contrast, Mr Brown said: “We will not be boycotting the Olympic Games. Britain will be attending the Olympic Games ceremonies. The Dalai Lama has not called for the boycott of the Olympics.”

Mr Sarkozy admitted that there were still tensions over the Common Agricultural Policy but said that for the first time a French president was prepared to debate its future.

Meanwhile Buckingham Palace accepted the blame for what it described as a “minor mix-up” that meant that Mr Brown failed to show up for a photograph before Wednesday’s state banquet. The Queen was heard to ask: “Has the Prime Minister got lost?” after Mr Brown failed to appear alongside the heads of state at the event.

As the monarch and the French President looked around for him, Mr Sarkozy reportedly smiled and remarked to his wife, Carla: “That’s Gordon.” Royal sources confirmed that Palace officials had “misdirected” Mr Brown to sit down.

— While the French media broadly hailed the London trip a success, hackles were raised by Mr Sarkozy’s declaration that Britain’s record for the past 30 years was a model that France must follow.

A Le Monde columnist called this “a shameless exercise in toadying intended to win, at whatever cost, the approval of his audience”.

Le Figaro talked of a “Franco- British honeymoon” but said that it was up to Gordon Brown now to accept France’s hand.

France was also bemused by the collective swoon of the British media at the arrival of the President’s new supermodel wife. “The English conquered by Carla,” said a headline in le Parisien, under its story on “L’opération séduction du couple Sarkozy à Londres”.

When diplomacy can be a touchy subject

— Paul Keating, the former Australian Prime Minister, put his arm around the Queen during her 1992 tour to the country, earning himself the nickname “Lizard of Oz”

— Geri Halliwell, a member of the Spice Girls, was scolded for turning up 40 minutes late to meet the Queen at a Buckingham Palace reception in 2005. She also pinched the Prince of Wales’s bottom

— In 2004, when Jacques Chirac, was French President, he was admonished by Britain’s tabloids for almost touching the Queen. One headline read “Hands off!” and the accompanying story described how Mr Chirac “came within a whisker of manhandling The Queen”

— Last year President Bush mistakenly said that the Queen had helped to celebrate the US bicentennial in 1776, rather than 1976. He didn’t help the situation by winking at the monarch, earning him a disapproving look described by the President as one “only a mother could give a child”

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