“CONVERSATION of the week”, posted on a backroom wall at the US Embassy on Grosvenor Square in London, made me laugh out loud. It came from the questioning of a visa applicant about his former drug use.

“Do you still like marijuana?” asks the interrogator. “Oh, yes, a bit,” he replies, astoundingly (and perhaps a little too honestly).

“Do you intend to smoke marijuana in the future?” comes the follow-up question. “Possibly — but not near the airport or near customs, because they always want to chase you,” comes the response.

US immigration officials, it seems, have a sense of humour after all. And John Brennan, the jockey-sized chief of visa services at the US Embassy, is determined to change the image of the visa department — which has been criticised in the past for long waits and sometimes surly service.

On a behind-the-scenes tour this week, Brennan proudly points to the new public coffee machines. “Sometimes people complain they don’t have enough time to drink it,” he jokes. “That’s how quick we can be now.”

There are 25 booths for visa interviews — three times more than before 9/11 — and a waiting room that has doubled in size in the same time. Applicants typically wait for about two hours, Brennan says, but the wait can be less than an hour, although four-hour hold-ups have been known.

We pass a red “refusals” tray, a large Stars and Stripes and a pile of International Herald Tribunes before reaching the booths, beyond which, in the airport lounge-style waiting room, I spot a woman reading Bill Bryson’s Notes from a Big Country, his bestselling travel book on America.

In front of us, a man is having a fingerprint scan, the first phase of “biometric” testing, standard now for visa applications — most tourists do not need visas as they are eligible for visa waivers. “See, there you go,” says Brennan. “We took in all that information in just 35 seconds.”

The friendly attendant tells the applicant: “Have a fun time, now!” Then we pass a woman explaining that she was a reformed character after a shoplifting offence when she was much younger. “How long ago exactly was that?” asks the sharp-eyed official.

“We’re trying to improve the speed of everything here,” said Brennan, who looks a bit like one of the officials from the Tom Hanks film The Terminal in his grey pin-striped suit, red tie and brogues, as he shows us the latest model of a ten-finger scanner, which is being introduced to replace the current two-finger model during the next year.

“The customer service is more or less right now. I tell you it’s got a lot better in the past year” — after I had told him about my four-hour-plus wait 12 months ago — “security with a smile, that’s what we’re aiming for . . .”

Just don’t tell them about that trip to Jamaica you made when you were a student.

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