Parts of Dublin will be on lockdown for most of the day ahead of a showcase cultural event in the evening, where the 44th US president will address tens of thousands of people at College Green.
A host of stars from the arts and sports worlds as well as musical groups are to entertain crowds, who have been warned to arrive early.
Government sources confirmed last night that the Irish and American leaders would be raising a number of issues during their bilateral talks.
Tánaiste Eamon Gilmore has already said the Government was likely to raise the plight of tens of thousands of Irish workers in America and plans to reform immigration there, through visa changes.
Mr Obama will fly into Dublin Airport at 9:35am on Air Force One and with his cavalcade will drive to Áras an Uachtaráin in the Phoenix Park.
After a meeting with President McAleese, he will then meet Mr Kenny and Mr Gilmore in Farmleigh.
The US is Ireland’s largest trading partner and also the largest source of investment, creating an estimated 89,000 jobs here. Ongoing trade between the two nations will form part of the talks.
Mr Obama is then set to fly to his ancestral home of Moneygall by helicopter, arriving at about 3.15pm.
But with mixed weather conditions forecast for today, the Department of Foreign Affairs confirmed that alternative plans are in place if strong winds prevent the air trip.
Both are expected to walk through the town, stopping at the ancestral home of Mr Obama’s great-great-great grandfather, Falmouth Kearney. He will also meet extended family members during a visit to Ollie Hayes’s pub.
Mr Obama will then return to the capital, where he is due to address crowds at Dublin’s College Green at 5.30pm. Gates will open for the free event at 2pm.
There were suggestions yesterday the president may give his public address in Dublin from behind bullet-proof glass — although this could not be officially confirmed.
Machinery could be seen lifting what appeared to be bullet-proof glass into place on College Green yesterday.
An array of guests have been confirmed to entertain crowds, including Imelda May, Westlife, The Saw Doctors, the National Chamber Choir and The Coronas. Stars who will make an appearance at the free event include actors Brendan Gleeson, Saoirse Ronan, Daniel Day Lewis, Gabriel Byrne and sporting legends Brian O’Driscoll, Katie Taylor and Padraig Harrington.