The world’s worst terrorist attack could affect yachtsmen in the UK who could now face increased insurance premiums, it was revealed at the Southampton Boat Show.

Rumours gripped the insurance industry in London following Tuesday’s ‘flying bomb’ attacks on the World Trade Centre in New York and the Pentagon in Washington.One broker, it is believed, was advised to put up his premiums by 35 per cent immediately.

After the Piper Alpha oil rig explosion and the UK hurricane in the later 1980s Lloyds syndicates faced massive claims. Yet those two disasters at around 6 billion (pounds sterling) could be more than doubled by the American catastrophe.

‘It is reputed that the cost of these incidents could be as high as 20 billion pounds,’ top insurer Chris Knox-Johnston told YM.