Further to your previous correspondence, the situation regarding use of the Electronic System for Travel Authorization (Esta) for entry into America isn’t quite as clear as the US Embassy implies.

On a recent trip to Chicago, all four members of our group (UK passport-holders) had applied successfully online through Esta. As a result, we declined the green I-94W form on board. At immigration, we were told that all passengers were required to complete the green visa-waiver form as well.

The simplest option would appear to be to ignore Esta until it is mandatory and use the old green form. Clearly, increased bureaucracy is an aid to security. Phil Hughes, Buckinghamshire

The US Embassy replies: “We can understand why travellers would think it would be inconvenient to fill out both an Esta form and a green I-94W card. For now, though, it remains necessary. The green I-94W forms will be phased out, hopefully over the next few months, but until all airlines have fully implemented the Esta software throughout their entire networks, those forms will serve as a backup.

“Unfortunately, ignoring Esta is not an option. Passengers who arrive at the airport without Esta approval risk not being able to board their flights.”

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