Obamas meet UK royals to seal 'special' relations

US President Barack Obama was treated to royal pomp at Buckingham Palace on a two-day state visit aimed at ensuring the United States and Britain keep the "special" in their relationship.

Obama, on a four-nation European tour, heard a 41-gun salute at an elaborate arrival ceremony and was given a tour of the palace portrait gallery by Queen Elizabeth and her husband, Prince Philip. A state dinner was to conclude the day.

After laying a wreath at the Tomb of the Unknown Warrior at Westminster Abbey, he spent part of the afternoon playing ping pong with British Prime Minister David Cameron and students.

"Who wants to take me on?" Obama said as he walked into the Globe Academy, a school with a high proportion of low-income students.

He and Cameron played with each other against two students. At first the two left-handed leaders had some trouble getting their strategy coordinated.

"Are we keeping score?" Obama asked at one point. It seemed the students got the better of the two leaders.

Obama is on the second stop of a four-nation European tour, arriving from Ireland late on Monday and planning to attend a Group of Eight summit in Deauville, France on Thursday and end the week in Poland.

Ceremonial cannon sounded 41 blasts as Obama and his wife, Michelle, joined the queen, Philip, heir to the throne Prince Charles and Charles's wife Camilla, Duchess of Cornwall, on the Buckingham Palace west terrace for a formal arrival ceremony.

While the two governments have some differences over such issues as Libya, for example -- where Obama is seen as less eager than Europeans to lead the battle -- he and Cameron stressed the unique status of US-British relations in an opinion article in the Times of London.

"Not just special, but an essential relationship," they wrote. "It's not only history that binds us. Whether fighting wars or rebuilding the economy, our needs and beliefs are the same."

Obama and Cameron are to announce the formation of a US-British national security council to work together on international challenges and share intelligence, an Obama administration official said.

Obama spent Tuesday getting accustomed to Buckingham Palace for only the second ever state visit by an American president to Britain. George W. Bush made the first in 2003.

The Obamas were treated to a formal luncheon then afterward joined the queen and Prince Philip for a tour of the palace portrait gallery, reviewing pieces from the collection laid out for them.

Obama lingered over a page from the personal journal of George III, dated sometime around 1783, when the American colonies were fighting the British.

"America is lost! the king wrote, going on to muse about the possibilities of trade with the Americans and the importance of "a future friendship and connection."

In an exchange of gifts, the Obamas gave the queen rare memorabilia of a visit by her parents King George VI and Queen Elizabeth to the United States in 1939. The royal family gave Obama letters between Queen Victoria and U.S. Presidents.

The Obamas are staying in the Belgian suite, a half-dozen rooms last used by Prince William and Catherine Middleton on their recent wedding night. The Obamas met privately with the royal newlyweds, who did not attend the arrival ceremony.

The new US-British security council will help enable "a more guided, coordinated approach to analyse the 'over the horizon' challenges we may face in the future," the Obama administration official said.

In the past decade, London was Washington's only big ally at war in Iraq. The two countries field the largest contingents in Afghanistan, and more recently, along with France, have led a Western air war in Libya.

A speech at Westminster Hall on Wednesday may give Obama an opportunity to outline how Washington now views Europe in a crowded diplomatic agenda dominated by challenges from Asia to the Middle East.

A challenge for the two leaders is Libya. Obama, Cameron and NATO allies launched an air campaign in March to protect Libyan civilians from leader Muammar Gaddafi after an uprising. Obama, Cameron and French President Nicolas Sarkozy say they will not stop bombing until Gaddafi leaves power.

Obama and Cameron are also expected to review the fight against Islamist militants and relations with Pakistan after the killing of al Qaeda leader Osama bin Laden by U.S. special forces on May 2 on Pakistani soil.

Obama's visit to Britain follows a cheerful stop in Ireland, where he sipped a pint of Guinness in the village of Moneygall to celebrate ancestral roots there and used a speech in Dublin to lift Irish spirits bruised by a severe economic downturn.

As a precautionary measure, Obama flew to London on Monday night instead of Tuesday morning because of fears that a volcanic ash cloud from Iceland could drift over Ireland and prevent his Air Force One jet from flying.