WALKING up Whitehall, one could be forgiven for thinking that martial law has suddenly been declared.

Trying to get from A to B in the heart of the UK capital is not easy at the best of times but now roads are blocked off, pavements sealed and barriers erected while the usual groups of tourists have grown into battalions of bemused visitors, all huddled onto one side of the busy thoroughfare.

The Olympic lock-down has begun. Walking past the Treasury, the innocent pedestrian is met by what can only be described as an Army checkpoint. "Pass, please sir," said one soldier in his camouflaged gear. "Er, I don't have a pass, so what do I do?"

A finger pointed back in the direction I had come. So I retraced my steps up Whitehall.

"You can't use that pavement, sir!" barked another squaddie. My patience was beginning to thin.

As I passed Horseguards Parade, the penny dropped: most of the area has been sectioned off for the women's beach volleyball contest.

Late for a meeting, I looked on the bright side. Whitehall 'sources' have indicated members of the Scottish parliamentary lobby could watch the volleyballists from the top floor of the Scotland Office. Journalism has its uses.