Gone were the trademark sunglasses and the ubiquitous cell phone
Sarkozy played the statesman Wednesday as he began a two-day tour, greeting Queen Elizabeth II, and inspecting rows of cavalrymen as he prepared for key talks on defense, the economy and immigration.
After a round of ceremonial duties, he gave a fiery speech to a joint sitting of Britain's House of Commons and House of Lords. Sarkozy followed a powerful tribute to Britain's role in countering the threat of fascism in Europe with a promise to stand by London's side as it fought against the Taliban in Afghanistan.
"We cannot afford to lose Afghanistan," Sarkozy said, speaking in French. "Whatever the cost, whatever the expense, we cannot afford it."
He said he would pledge more French troops for NATO's mission in Afghanistan during a summit next week in Bucharest, Romania - if allies offer Afghans more responsibility and better coordinate nonmilitary efforts.
Canada has warned it will pull its 2,500 soldiers from Afghanistan if other allies do not offer more help. It wants 1,000 more troops for anti-Taliban efforts, while the United States has appealed to its NATO allies to bear a greater share of the war-fighting in the region.
The U.S. welcomed Sarkozy's announcement. The Times of London quoted President George W. Bush as saying Wednesday that the French offer almost certainly guaranteed that the upcoming NATO summit would be a success.
Sarkozy won a standing ovation following the 45-minute speech, which called for Britain and France to cooperate more closely in Europe and to work together to press the U.S. over action on climate change.
"Who better than its closest, sincerest friends to remind the U.S. of its responsibilities?" he said.
The pomp - and the opportunity to appear dignified - is important to Sarkozy amid a sagging approval rating at home and questions about his attitude.
British Prime Minister Gordon Brown plans lengthy discussions with his counterpart on Thursday about Afghanistan, as well as on a possible joint nuclear energy project, climate change and the international response to the recent unrest in Tibet.
But Wednesday's schedule focused mainly on pageantry, not politics - and the public's gaze was fixed on Sarkozy's glamorous wife, the model-turned-singer Carla Bruni-Sarkozy, who curtsied to the queen and chatted animatedly with her as the French couple arrived at Windsor Castle.
Bruni-Sarkozy, in a demur belted gray Christian Dior coat and matching pillbox hat, smiled as Prince Charles kissed her gloved hand in greeting as he met the visitors at London's Heathrow Airport.
"It was like a French Catholic schoolgirl meets Jackie O," said Lucy Yeomans, editor of the fashion magazine Harper's Bazaar, likening Bruni-Sarkozy's outfit to the famously stylish former U.S. first lady Jackie Kennedy.
Britain's tabloids, however, greeted Bruni-Sarkozy in typical style - printing a nude photograph she posed for in 1993. The original print is due to be auctioned in New York next month by Christie's auction house.
Sarkozy's 36-hour trip is the first state visit to Britain by a French president in 12 years. He is a guest of the queen, and will deliver a speech in full ceremonial dress at an official banquet.
The queen has bestowed Sarkozy with the Order of the Bath, a ceremonial British honor, and gave him a framed book of British stamps, her office said. In return, the French leader offered her a copy of "Perfect Knowledge Of Horses," a book published in France in 1743.
On previous foreign trips, Sarkozy casually checked his cell phone for SMS messages and was last month caught making an undignified outburst at a French agriculture fair, chastising a member of the crowd with expletives.
But the French leader, nicknamed the "bling-bling president" because of his extravagant tastes, appeared in serious mood as he reviewed a guard of honor in Windsor and laid a wreath at the Tomb of the Unknown Warrior at Westminster Abbey. Wearing a white tie and a red sash, Sarkozy toasted the British monarch at a lavish state banquet at the castle's St. George's Hall later Wednesday.
"My wife and I will never forget this visit," he said, raising his glass to the queen and to the "brotherhood" of French and British people.
With France worried about a stagnant economy, Sarkozy's approval ratings have dropped to around 40 percent from a high of around 65 percent in July. The opportunity to appear presidential during his visit to Britain could give him a domestic boost, French analysts claim.
His focus Thursday will be on meetings with Brown and a summit with a host of French and British ministers at London's Emirates Stadium, home of the popular Arsenal soccer club - seen as symbolic because it is an English team with a French manager and some top French players.
Ministers plan to use the summit to discuss slow progress on a joint call for a 26,000-strong peacekeeping unit of U.N and African Union troops for Darfur and reforms of international institutions including the World Bank.
Sarkozy, who said Tuesday he could "not close the door to any possibility" of a boycott of the opening ceremony of the Beijing Olympics, is likely to raise China's handling of protest in Tibet. Brown insists he will attend the Olympics.
In his speech to Parliament, the French leader urged new dialogue between China's government and the exiled Tibetan spiritual leader, the Dalai Lama.