President Michael D Higgins has described London's Olympic stadium as an enormously impressive and beautiful architectural achievement.

He was speaking during a tour of the Olympic site on the second day of an official visit to London.

The Olympic Park and Athletes Village in east London is still under construction but many of the key facilities, such as the 80,000-seat stadium, are nearing completion.

The President was shown around the complex by the chairman of the Games organising committee, Sebastian Coe, who said preparation for this summer's games was on track but with still a lot of work to be done.

One of the themes of President Higgins' first overseas visit has been the role of the diaspora in the economic revival of the country.

Mr Higgins has said he will be as supportive as he can of the Government's initiative to enlist the Irish abroad in helping turn the economy around.

In an interview, he said every kind of experience in every generation of the Irish abroad should be explored.

Asked if he believed the Irish abroad should be able to vote in elections at home, he said the matter should be brought up when the forthcoming 'Constitutional Convention' gets under way.