Cross-channel train operator Eurostar has reported record passenger numbers for the first three months of 2004.
Eurostar has seen its market share increase in 2004
Some 1.6 million people used the service, an increase of 19% on the same period last year.
Eurostar says it has taken business from the airlines, partly due to the opening of its high speed link in Kent.
The news is likely to heighten tensions at tunnel owner Eurotunnel which is locked in dispute over whether to raise its charges.
Eurotunnel - a separate company to Eurostar - faces a revolt at its 7 April annual meeting from rebel shareholders calling for higher tariffs.
Led by maverick financier Nicolas Miguet, the shareholders have threatened to overthrow the company's board of directors.
But other shareholders have said the way to boost the company's share price is to cut charges to boost traffic through the channel.
Eurostar reported that on the London-Paris route it had a market share of 66% in February, compared with the same month last year.
On the London-Brussels route, Eurostar achieved a market share of 52%, against 38% for the same period last year.
According to the AFX news agency, British Airways saw a 11% loss of market share on the London-Brussels route.
This week Air France said was cutting fares for domestic and European flights in a bid to counter the threat from high-speed train services and low-cost carriers.
The airline also said it planned to use a system of "weekly" and "weekend" tariffs which offer reductions of up to 92% on fares and conditions for travel, such as a compulsory overnight stay on a Saturday.