Willie Walsh has slammed the Conservative Party plans for building a high speed rail link rather than a third runway at Heathrow.
The BA ceo said the idea that a link from Heathrow to Manchester and Leeds would be "an adequate substitute for a third runway is a notion that beggars belief."
Mr Walsh, speaking to the Insurance Institute of London, said the concept was"really quite shocking."
"Flights to Manchester and Leeds are less than 3% of Heathrow's current operation,"he said.
"Even if all passengers from these cities switched to rail (and many catching connecting flights at Heathrow might not), the runway capacity freed up would be swallowed almost immediately by natural growth."
He said the Conservative plans would "condemn Heathrow to permanent status as the most delay-prone airport in Europe."
Mr Walsh also challenged the environmental case for trains.
"And let us not forget that the green argument for high-speed rail can be over-stated," he said.
"High-speed trains are heavy beasts, and soak up a lot of electricity. French TGV trains are low on emissions because they use nuclear-generated electricity. Would a UK system do the same?
"And if the financial structure for this railway results in high fares, will the trains attract the loads they need to generate low emissions per passenger?"
Mr Walsh said high-speed rail should be seen as complementary to air travel, not a substitute for it.
He added: "That is why Paris Charles de Gaulle and Frankfurt airports already have high-speed rail links. And by 2011, they will also have four runways each - while Heathrow struggles on with two.
"A third runway at our national hub airport is essential for jobs, wealth creation and the future economic success of this country in a globalised economy."
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