An armoured limousine that carries US president Barack Obama and First Lady Michelle Obama got stuck on a ramp at the entrance to the American embassy in Dublin this afternoon.

The president’s heavily-armed Cadillac, nicknamed “The Beast”, came to a sharp halt as it exited the embassy’s Pembroke Street gate.

“As it drove out, the car appeared to have got its low underbelly caught on a piece of metal sticking up that a gate might lock into,” said a reporter at the scene.

The White House later said Mr Obama and his wife Michelle were not in the vehicle at the time. Crowds waiting outside the embassy for a glimpse of the president cried: "'ooh" upon hearing the crunch of heavy metal as the body of the car struck the ground. One man watching from the opposite side of the street shouted: "Need a push?"

Mr Obama and his wife switched to another car that then drove them to the Marine Force One helicopter that was to fly them to the president’s ancestral home in Moneygall, Co Offaly.

The Cadillac holds its own oxygen supply in case of chemical attack and is fitted with state-of-the-art communication technology.