Micky Flanagan: The ragged-trousered controversialist

The comedian tells Ian Burrell why he gave up teaching for stand-up and why he doesn't joke about Margaret Thatcher

Cockney comedian Micky Flanagan has just sold out 100 shows. People come to see him yank his long hair over his face, in the fashion of the modern teenage male, and shuffle across the stage like the scary "Chicken Children" who his audience recognise as the youths who congregate in urban British high streets with an insatiable appetite for fried fowl and chips.

And he does this gag, which plays to his working-class roots, about being offered only a tiny dish of tomato ketchup in a posh restaurant and taking a little taste before telling the waiter: "That's fine, bring me the bottle." And another one about leaving the house on a brief errand only to meet some mates and end up not just "out" but "out, out" in a nightclub in his carpet slippers.

It's this last routine that gives its name to his 160-date Out, Out Tour. The last 100 sell-outs have shifted some 150,000 tickets and Flanagan is in "fierce negotiations" with broadcasters to secure the right television show for his talents.

It's a critical moment for the former Billingsgate fish porter, and he is conscious that other stars of the comedy circuit have wrecked their careers after being tempted into telly. "Make no bones about it. Unless I can make the show I want, it's not going to happen," he says. "I have my audience now. Why would I make a shit TV show and fuck that up?"

Paradoxically it has been television, and specifically performances of the Chicken Children routine on Live at the Apollo and the ketchup routine on Mock the Week, that has fuelled his box-office success. "TV is king when it comes to putting bums on seats, and I've had to play the game," he says. "You get the opportunity to go on Michael McIntyre's Comedy Roadshow and five minutes before you go on they say 'You can't do that bit.' So you go out and do a nice 10 minutes of TV-friendly comedy. I want to be able to go on stage and say 'Who gives a fuck about the Royal Family and the accession?' Here's an idea, what about fucking the lot of them off? When are we going to get that vote?"

Anyone expecting Flanagan, 49, to offer an Alf Garnett patriotic sentimentalism towards a bygone East End is way off the mark. One of his trademarks is a bowling Cockney gait ("the Cockney likes to walk ab-aaht!"), now a rare sight on the Bethnal Green streets where he grew up. But though his mother danced with the Kray twins – "everyone says it but my Mum really did" – he's not interested in reminiscing about jellied eels and pearly kings. "I don't do dewy-eyed nostalgia," he says. "I really guard against doing a version of the Good Old Days when you could leave the front door open and Ronnie and Reggie would come in and torture you."

In fact, he describes himself as a former "Marxist-Leninist" and teenage member of Labour Party Young Socialists who, as an angry 14-year-old, took part in the first Anti-Nazi League marches in the late Seventies.

The night before we met he had been on stage in Glasgow. Discussing the Seventies with his audience, he remarked: "And then Margaret came along and it all went tits up..." Only about 50 people in the 2,000-strong crowd cheered. "They are your ratios now. And that's in Scotland! They don't mind you doing a Blakey impersonation, but you can't be having a go at Thatcher."

So he avoids "too much keep the red flag flying" because many fans either "don't want to hear it" or "don't agree with it". Even as he mentions politics now he raises his fist in parody of a previous comedy era, shouting: "My name's Ben Elton, good night!" He says he sometimes looks in the mirror "like Robert de Niro" to remind himself not to get too earnest because "first and foremost I'm a stand-up". Even so, he dropped a joke about travellers "not doing a lot of travelling" because he was uncomfortable that it was provoking cheers rather than laughs.

After leaving school at 15 to work in the fish market, Flanagan later joined the furniture trade before heading to the Bethnal Green Institute to take an English GCSE at the age of 25. An avid reader, whose favourite book is Robert Tressell's The Ragged-Trousered Philanthropists, he signed up to the Open University, completed a degree in social sciences and became a teacher. But he then gave that up because "it was too much work for what you got paid". He went into decorating and started doing stand-up in the evenings.

After 15 years on the circuit, his time seems to have come. Aside from negotiations on his own TV show, he will be a team captain in The Mad Bad Ad Show, a funny take on the advertising industry for Channel 4 in the new year. Today his act contains more bourgeois references, such as the prices charged in delicatessens. "I don't like this idea that comedians have to hide aspects of their lives to remain somehow a man of the people," he says. "My wife did work at the V&A and did get a degree at the Chelsea School of Art. These are all real things; my real lived life. I'm not about to hide the fact that I've read a lot of books. It's a nod to saying it's OK to get an education and to have a wife who is completely your equal if not your superior – except I've got more money, ha-ha-ha."

Micky Flanagan always knew he wasn't going to be a political activist, but there are messages in his comedy. "I was not the sort of bloke who was going to walk around in a black duffel coat shaking a bucket. I'd probably have had one eye on the barmaid thinking 'Where's the party?'. I was always torn between enjoying my life and trying to think and do the right thing."

'Micky Flanagan Live – The Out, Out Tour' is available on DVD from 14 Nov