It's 10:30am and Oz Clarke is already onto his second or third pint of ale. It's entirely appropriate, for his presence in the Betjeman Arms, in London's St Pancras train station, is all to do with launching Cask Ale Week, the brewing industry's promotional drive for the frothing liquid that he's merrily swigging.
His commitments are nevertheless taking their toll on a man who has been one of the most prominent ambassadors for British drinks in recent times.
"It's nice to have a good breakfast beer, but it feels like I've been on the go for ages," says Clarke, one of the hosts of boozy TV show Oz and James Drink to Britain.
The James of the title is of course Top Gear's James May, and just the prospect of a strenuous morning's drinking had, it seemed, proven too much for him. He had not turned up for his promised appointment with the assembled crowds.
Ripe for conversion
Never mind, Clarke was more than enough for the arriving Eurostar travellers in the terminal who were the target audience for this first Cask Ale Week initiative.
The Europeans hopping off the train were ripe for being converted into cask drinkers, the organisers hoped, and Clarke was in full agreement that cask beer and the pubs in which it is served are worthy of finding a larger audience.
You would have to have been living under a pewter tankard to have missed the fact that cask is one of the few on-trade success stories of the past few years, and represents one of the greatest hopes of pubs pulling themselves out of the doldrums.
Celebrity wine writer Clarke was one of the big name backers of an initiative bidding to help turn that hope into reality.
"I just believe in all this," he says, gesturing to indicate the sampling activity, chattering punters and Cask Ale Week promotional material all around him. "I believe in pubs' importance to their communities. I like the fact that, in this period where binge-drinking hangs like an enormous monkey around our shoulders, we should still be able to accept alcohol as a pleasant social drug in the pub because it's an environment where nobody gets out of control.
"Cask is fundamental to that aspect of pubs, and because it's a local product, it's fundamental to that sense of community."
The appeal of local provenance has been picked out by many as one of the main reasons why cask beer is faring well compared to other categories.
Drinking local
Clarke is a big fan of drinking local, but is also realistic about the growing consolidation in brewing - the big business that means the industry has the means to run schemes such as Cask Ale Week. "We need the healthy and aggressive companies that we have today," he says.
"Greene King, for example, gets a lot of knocking because it is very avaricious in its national expansion.
"At the end of the day, I would rather drink Batemans if I go to Lincolnshire, Arkells if I'm in Swindon, but if all the pub has got is Greene King IPA, I will happily drink it."
The big, the small, the local and the multi-national were all featured in Drink to Britain. All these diverse players have shaped a drinks industry for which Clarke is full of praise.
"Britain has more drinks at a world class level than anywhere else in the world," he says. "Ok, the French have their wine, but we do world class beer, we do gin, we do cider, and we're the only country in the world to do perry."
His passion and support is almost enough for us to let him and James May off choosing tea as their "drink of Britain" at the conclusion of the TV show.
Why St Pancras was the perfect place to launch Cask Ale Week
Oz Clarke was literally standing on beer history when he opened Cask Ale Week in the Betjeman Arms on April 6.
In the 1860s, when St Pancras was built, there was growing demand in the capital for the beer being brought down on trains from that epicentre of brewing, Burton-upon-Trent. With the soft water of Burton making for clearer and crisper ale than the darker, more robust stouts and porters downed in London at the time, it was a revolution.
So St Pancras architect William Barlow decided to incorporate a vast beer storage area into the bowels of the station, a design that explains the structure of the refurbished station today.
Barlow even positioned the cast-iron columns that support the station's roof to match the plans of beer warehouses in the Midlands. The spacing of just over 14 feet between them is a multiple of the width of the casks.