US President Barack Obama left yesterday on a major European tour mixing pomp, personal history and great power diplomacy shaped by the historic uprisings raging through the Arab world.

Mr Obama is seeking support for his plan to spur democracy after revolts in Tunisia and Egypt and may face pressure from Europe for a more robust US role in Libya as the Atlantic alliance is updated in an era of new challenges.

The President will journey to ancestral home turf in the tiny village of Moneygall in Ireland, bask in the splendour of a state visit with the Queen of Britain, meet world leaders at the Group of Eight summit in France and visit Poland.

Despite suggestions Mr Obama prefers Asia to Europe, the President has repeatedly trekked across the Atlantic, and aides say he is firmly committed to the world’s most successful continental alliance.

“This is a very important trip for the President to reaffirm our core alliances in the world (with) our European allies,” said Ben Rhodes, a deputy US national security adviser.

Mr Obama’s election, after the George W. Bush years, was greeted with euphoria in Europe, both sides may have reason for disappointment in the Obama Presidency so far.

Europe perhaps did not get the president it hoped for, as Mr Obama failed to close the “war on terror” camp at Guantanamo Bay, saw his climate change initiative collapse and appeared to look to booming Asia for America’s future.

The White House was frustrated that calls for more European combat troops for Afghanistan rarely materialised and looked on as its hopes for more burden sharing waned as indebted allied governments slashed military spending.

Meanwhile, Queen Elizabeth II will roll out the red carpet for Barack and Michelle Obama’s state visit this week, as a special royal relationship flourishes with the US first family.

The Obamas will arrive in the UK tomorrow as part of the European tour and will visit the Queen, two years after they first met and shared an unusually public display of affection.