The general mood may be one of determined defiance, coupled with a heightened sense of trepidation, but according to analysts, the terror attacks in London will impact the tourist industry, albeit to a lesser degree than 9/11.

International travel bookings are expected to soften slightly, though in the immediate weeks following the attacks, there seemed to be few cancellations of already-booked holidays to the capital.

But based on recent experiences with such atrocities - such as the commuter train bombings in Madrid in March 2004 that killed 191 - visits to affected regions wane.

The difference in scale between terrorist attacks on the US in 2001 and Madrid and London over the last 18 months will be reflected in the reaction of the tourist industry, officials believe. Whereas tens of thousands cancelled holidays following 9/11 and thousands more returned home from abroad early, a much lesser impact will be felt following 7/7.