World leaders lined up on Tuesday to pay tributes to Barack Obama on the occasion of his inauguration as the 44th president of the United States, with the new president drawing comment from America's allies across the globe - as well as from current enemies.

In the Middle East, where American stock has fallen furthest in recent years, guarded welcome for the president-to-be was evident.

Iran expressed a hope that Barack Obama will "choose the right path" toward Iran, ISNA news agency reported Tuesday.

Cairo  - Across the Arab world, many greeted Barack Obama's victory in the US presidential election with jubilation and relief.

But 10 weeks later, as Obama is sworn into office as the 44th US president and the first African-American to hold the nation's highest office, people from across the Arab world say they are greeting Obama's presidency with diminished expectations.

Wash

Washington  - Moments after taking the oath of office, US President Barack Obama declared Tuesday the United States had ushered in a "new era of peace" and urged Americans to accept a greater responsibility to tackle the vast challenges confronting the nation.

"Starting today, we must pick ourselves up, dust ourselves off, and begin again the work of remaking America," Obama told millions of cheering onlookers lined along the National Mall, Washington's vast park that stretches from the inaugural site on the Capitol steps to the Lincoln Memorial.

Washington - Long before sunrise, with the crescent moon still high in the sky, inauguration revellers left warm homes to stand in long, cold lines and ride packed trains to the once-in-a- lifetime event unfolding Tuesday in the nation's capital.

Unprecedented numbers - the final count could reach 2 million - gathered to celebrate the presidency of Barack Obama, 47, the nation's soon-to-be first black president who many said was bringing them hope after eight gloomy years of the George W Bush presidency.

Washington - Don King, the controversial boxing promoter known for using the slogan "only in America" to describe his rise from a second-degree murder conviction to the pinnacle of the sport, says he believes Barack Obama will restore United States' standing in the world.

"It ain't just an election for America, it's an election for the world," said King, who earned millions of dollars over decades promoting fights that included greats Mohammed Ali, George Foreman, Mike Tyson and Evander Holyfield.

King spoke with Deutsche Presse-Agentur dpa while attending Obama's inauguration Tuesday at the Capitol building.