Obama and the first lady arrived in London late Monday, 12 hours early because of a volcanic ash cloud that is disrupting air travel.

    But Tuesday they were back on schedule, with a day marked by the pomp and pageantry that typifies state visits to Britain.

    London's streets were cleared for the presidential convoy's high security trip to Buckingham Palace, the royal family's main residence.

    There, Obama and his wife were met by Queen Elizabeth and her consort, Prince Philip.

    The group have met before, two years ago, and Mrs. Obama even brought the couple's two daughters to England for a recent trip.  But this is the first state visit by the president and his wife.  The U.S. president was honored with a 41-gun salute and, in the palace gardens, the United States national anthem.

    State visits are an important form of diplomatic contact between nations, and this trip is designed to show the close relationship between Britain and the United States.

    When asked a few Britons had opinions about the strength of the relationship.

    "I think it is pretty good.  They both help each other out with the wars and politics and everything," said one man.  "Barack's very involved with our parliament, as we are with America.  We have helped to fight terrorism and a lot of holiday people leave here to go to America.""There tends to be the thought that Britain still thinks that we are a bit of a superpower when we are not really anymore," said another man.  "But America is and it is good to be allied with the most powerful country in the world, we would be stupid to turn our backs on that.""I just think certain prime ministers of our country have not always hit it off with presidents," one woman said. "It has to be a warm relationship and obviously there are personalities that do not always hit it off amazingly, but I think the present leaders do."Britain's Prime Minister David Cameron and his wife hosted Mr. and Mrs. Obama at Downing Street.

    The two elected leaders have plenty to discuss.  At the top of the agenda is the ongoing crisis in Libya, Afghanistan, and Israel-Palestine, as well as the Arab Spring and Iran's nuclear ambitions.

    Those conversations will be addressed further on Wednesday when Obama is to hold talks with British politicians and address Britain's parliament.

    But for Tuesday evening, the president’s plans call him back to Queen Elizabeth at Buckingham Palace, where he and Mrs. Obama will be guests of honor at an evening banquet, sure to be marked with the same splendor and ceremony as the day’s events.(本文由在线英语听力室整理编辑)