WASHINGTON (AP):

President Barack Obama, touting his own Irish ancestry, hailed Ireland on Monday for having as much influence on United States culture and tradition "as any country on earth". As fountains on the White House lawns ran green for the day, Obama's affinity for Ireland bubbled over.

"This is an affirmation between one of the strongest bonds between peoples that exists in the world," Obama said as he met in the Oval Office with the Irish prime minister, Brian Cowen.

And Obama boasted of Irish ancestry, saying: "I, personally, take great interest on St Patrick's Day because, as some of you know, my mother's family can be traced back to Ireland."

Less high-profile gathering

The president also met with Northern Ireland's First Minister Peter Robinson, a Protestant, and his Catholic deputy, Martin McGuinness, in a less high-profile gathering in his national security adviser's office. Tensions are high in Northern Ireland, where Irish Republican Army splinter groups killed two soldiers and a police officer this month in the first attacks of their kind since 1998, when the landmark Good Friday Agreement was reached.

From appearance to agenda, the White House was in an unmistakable Irish mood.

First Lady Michelle Obama had green dye put the fountains on the White House's North and South lawns, said spokeswoman Katie McCormick Lelyveld. She was inspired by her hometown of Chicago, where the city marks the national holiday of Ireland by dyeing the river green.

Elsewhere in the United States, other cities and towns honoured Ireland with their own signature celebrations, taking a break from worrying about the global economy to enjoy a day of shamrock-themed frivolity.

Organisers predicted 200,000 participants - and as many spectators - would be along New York's Fifth Avenue for the city's 248th St Patrick's Day parade.

In Portland, Maine, 75 people greeted the day with an icy plunge in the Atlantic Ocean, charging into the 37F (2.78C) water at a beach and celebrating with a Guinness afterward.

Many cities with big Irish communities, like Boston and Chicago, had their celebrations over the weekend.

In Indianapolis before dawn, Mayor Greg Ballard and other dignitaries dumped dye in the city's downtown canal, triggering a fountain of green water before the city's midday parade.

Giving away some green

In Los Angeles, a Roman Catholic priest celebrated St Patrick's Day - and his 90th birthday - by giving away some green. Father Maurice Chase went to Skid Row with a wallet packed with $20 bills to give to some of the city's neediest residents. About 300 people lined up for cash.

And in Savannah, Georgia, masses of revellers clad head-to-toe in green crammed sidewalks and oak-shaded squares for the best parade view.

The New York St. Patrick's Day Parade started in 1762 as a modest foot parade, and still shuns commercial aspects like floats or cars.

The parade goes past Saint Patrick's Cathedral at 50th Street and continues up to the American Irish Historical Society at 86th Street. It is led by a unit of soldiers - the 'Irish Infantry' - and is officially sponsored by the Ancient Order of Hibernians.

In Manhattan, the yearly ritual creates a traffic gridlock, with pedestrians allowed to cross the parade route only at police-guarded points.

New York City Mayor Michael Bloomberg summed up the spirit of the day.

"I can't think of any better time for a parade, when some people are distressed and some people are disappointed and some people are depressed," he said. "People need a pick-me-up, people need to know that we can get through this together."

In Washington, Obama and the Irish leaders also attended a congressional luncheon celebrating the holiday. Obama, the leader of the House of Representatives, Speaker Nancy Pelosi, and Cowen paid tribute to Senator Edward M. Kennedy, who is being treated for a brain tumor and was unable to attend. Cowen said Kennedy was "our most special Irishman."

Hailed from small village

Obama said he learned last year during the campaign "that my great-great-greatgrandfather on my mother's side hailed from a small village in County Offaly." The ancestor came from the village of Moneygall. County Offaly is in the southeastern province of Leinster.

Obama joked about putting the apostrophe after the 'O' in Obama and suggested Barack was an ancient Celtic name. Addressing Cowen, he said, "I hope our efforts today put me on the path of earning that apostrophe."

The Irish guests were invited back to the White House for a cocktail reception Tuesday night that the president's aides say will be equal parts diplomacy and revelry.

For the evening event, Pulitzer Prize-winning poet and Northern Ireland native Paul Muldoon was to be featured. The White House also invited Maggie McCarthy, a traditional Irish dancer and musician from Cork, and vocal group Celtic Thunder. The Shannon Rovers, the official pipe band of Chicago's St Patrick's Day festival, also were set to perform.