"Heathrow is the UK's only hub airport and a strategically important national infrastructure asset. Heathrow faces stiff competition from other European hubs and we must continue to improve the service we offer passengers and airlines.
"We have invested billions of pounds in new facilities such as Terminal 5 (T5) in recent years and passengers say they have noticed the difference. Our plan for a further £3 billion of private-sector investment will further improve the airport for passengers. The plan represents good value for money for airlines and passengers and comes at no cost to taxpayers."
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