Eurostar has seen an 18.3 per cent increase in passengers in the first half of the year, but is warning that its growth may slow as a consumer downturn starts to bite.

Rising air fares and faster journey times between London and the Continent are encouraging more passengers to opt for the train, with traveller numbers for the first half of the year hitting 4.63 million.

Ticket sales between January and June totalled £368.8 million - an increase of 24.7 per cent against the same period in 2007.

Growth in traveller numbers was greatest in towns and cities to the north of London, since Eurostar's move into the new St Pancras International station last autumn.

Derby, where passengers can buy a through ticket to Paris from £79, has seen a 190 per cent increase in passengers, while Nottingham has seen passenger numbers increase by 131 per cent.

Richard Brown, chief executive at Eurostar, said: "The impact of rising oil prices on air fares, combined with growing awareness of the much greater environmental impact of flying, are causing more and more travellers to switch from plane to train."

“However, whilst we expect traveller numbers and ticket revenues to continue to rise, it is clear that the wider economic environment is deteriorating and we expect that the rate of growth will slow in the second half of the year,” Mr Brown said.

Eurostar is to add an extra daily services from London to Paris on 8 September, taking the number of daily services between the two capitals to 18. In the first six months of 2008, Eurostar said that 92.6 per cent of its trains arrived on time or early. This compares with an average of 62.3 per cent of flights on routes from London to Paris or Brussels between January and April 2008.

Although Eurostar travellers for the year are likely to be in excess of 9 million, the fast train service which travels through the Channel Tunnel still carries about 4 million fewer passengers than were originally envisaged when the French and British railways first proposed plans for a high-speed cross-Channel rail link in the 1980s.

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