LONDON -- It's not every day the American president's driver is told to move his bulletproof car.
But Queen Elizabeth II's handlers made the request Wednesday after President Barack Obama's reinforced Cadillac limousine was found to be blocking the garden entrance driveway at Buckingham Palace.
After it was moved, Jaguars carrying Prince Charles and other members of the royal family pulled up for the queen's reception for leaders attending Thursday's G-20 summit.
Obama and his wife, Michelle -- wearing a black and white dress, pearls and a black coat -- were two of the first dignitaries to meet the queen, who wore a salmon-colored dress and her trademark pearls.
During their private meeting, President Obama and first lady gave the queen a personalized iPod with video footage of her 2007 visit to Washington and Virginia. She was also given a rare songbook signed by composer Richard Rodgers.
In return the queen and her husband, Prince Philip, gave the Obamas a signed portrait of themselves.
Queen Elizabeth has met with 11 of the last 12 U.S. presidents, including a meeting that took place with Harry Truman when she was a princess, according to Buckingham Palace spokesman David Pogson.
The only president she did not meet was Lyndon Johnson. His widow later met the queen.
The queen and her husband entertained the Obamas in her private audience room, which overlooks the palace gardens where thousands of daffodils and other flowers were in bloom.
After her meeting with the Obamas, the queen held a reception for all the world leaders attending the summit.
They gathered in the palace's picture gallery and were served champagne, wine and canapDes of chicken with zucchini on skewers, mini Cornish pasties, smoked quail eggs, foie gras and tiny rolls of duck filled with melon.
The queen chatted with Italian Prime Minister Silvio Berlusconi while French President Nicolas Sarkozy held an animated discussion through an interpreter with US Secretary of State Hillary Rodham Clinton.
Prince Charles shared a joke with Brazil's President Luiz Inacio Lula da Silva while his wife, Camilla, held a long talk with Mrs. Obama.
"It was a wonderful visit," Obama shouted to reporters as he and his wife left the palace. "Her majesty is delightful."
Several hundred people gathered outside Buckingham Palace and cheered as soon as they saw President Obama.
Earlier in the day, Obama used a press conference with Prime Minister Gordon Brown to say how much he and the first lady were looking forward to meeting the queen, praising her as a model of "decency and civility."
Brown and his wife, Sarah, were holding a dinner at Downing Street for all of the leaders attending the summit.
Celebrity chef Jamie Oliver was cooking dinner for the G-20 leaders. The main course was slow-roasted Welsh lamb accompanied by wild mushrooms, asparagus and potatoes from Jersey in the English Channel. Vegetarian leaders were being offered potato dumplings and asparagus.
Appetizers include baked Scottish salmon with vegetables and goat's cheese from Hertfordshire with roasted shallots. Bakewell tarts and custard is on the menu for dessert.
France's Sarkozy, who had hinted he would walk out of the G-20 if leaders didn't agree to concrete plans on tighter financial regulations, was the last to arrive for the dinner.
At the spouse's dinner hosted by Sarah Brown, Mrs. Obama sat next to children's author J.K. Rowling.
President Obama was among the last world leaders to leave Downing Street following the working dinner.
"It was a wonderful dinner," Obama said as he left with wife, Michelle.
Sarkozy, who the last to arrive, was among the first to leave after the dinner.
He declined to comment to waiting reporters.