Heathrow chiefs BAA have denied claims work is already underway on Terminal 6 as the Government prepares to announce its verdict on expansion.
Speculation about plans for a third runway and sixth terminal being a 'done deal' is nothing new, but rumours surfaced this week that groundwork has actually begun.
Two readers contacted the Chronicle within days claiming builders were already tunneling and laying electric cables at the airport in preparation for T6.
However, a BAA spokeswoman insisted there was no truth in the rumours and people were confusing T6 with the new Heathrow East terminal, which already has permission and is due to open in time for the London Olympics.
"There's a lot of work going on around Terminal 2, moving electricity cables and supplies, to enable work to begin on Heathrow East next year," she said. "If the Government decides in favour of expansion at Heathrow, the earliest a third runway could be achieved would be 2020. We're certainly not doing any preparation work for that."
Twickenham MP Vince Cable said he very much doubted BAA would risk beginning work on the project at this stage.
"It wouldn't surprise me if advanced planning for T6 is being done but it would surprise me a great deal if BAA was engaging in a speculative investment on a terminal that may never be built," he added.
However, crane driver Gerald Brown, of Catherine Gardens, Hounslow, and management consultant Simon Broom, of Heath Gardens, Twickenham, remain convinced T6 is already being built.
Mr Brown, 43, who often works at Heathrow, said airport staff had told him the new terminal was a 'done deal' and tunnels he had seen being dug were part of the preparations.
Mr Broom, 50, said a friend doing consultancy work at the airport had told him workmen there were already busy putting the communications and IT infrastructure in place for T6.
"According to him, dozens of consultants and advisors from other companies are already on site undertaking paid work for T6 and discussing it 'as if it is already happening'," he added.