If the Coalition cock-ups and ministerial meltdowns appear particularly well-informed when political satire The Thick Of It returns, then Nick Clegg may wish to interrogate his private office.

Aides to the Deputy Prime Minister have been only too keen to leak embarrassing details of life as the Government’s junior partners, the writers of the Bafta-winning series have revealed.

The fourth series of Armando Iannucci’s acclaimed comedy, which spawned Westminster’s post-Budget buzz-phrase “Omnishambles”, will air on BBC2 next month.

Real life is reflected with the Opposition now in government but forced to share office-space with their ambitious junior coalition partners, known as “The Inbetweeners”.

Malcolm Tucker, the fearsome former No 10 enforcer, is at bay. In a shock turn of events, Nicola Murray, the previous “Dosac” department minister, has become Leader of the Opposition after accidentally winning an election through a block vote mechanism no-one can quite understand. Murray, although no less inept, is now Tucker’s boss.

There are big changes in Whitehall, where Peter Mannion, the world-weary opposition MP with more than a touch of Kenneth Clarke, finally takes over the Social Affairs department. But he has to live with a “Lib Dem” junior minister, keen to make his mark, who publicly contradicts any policies Mannion dares to put forward.

Did the producers have a high-grade Coalition source? Sean Gray, series writer, said: “Armando got an email after a political awards. The person said ‘I’m working in Nick Clegg’s office until June. I’ll let you know what happened after that.’”

Gray did not disclose if the offer was followed-up. His co-writer Roger Drew added that a female member of David Cameron’s press office also approached the writers at a Westminster screening of Veep, the HBO political satire that the pair penned with Iannucci.

Adam Tandy, producer, said: “We don’t think anyone had a meeting but we keep our ear to the ground. We don’t have any deep sources - apart from Nick Clegg.” The writers employ a political adviser based at the BBC’s Millbank studios who helps them gauge the mood of the Coalition.

Nicola Murray’s elevation was sealed after Ed Miliband won Labour’s leadership election. She was initially going to be deputy leader. Gray said: “Nicola has somehow gone from being inept to becoming leader through strange mathematics. Ed winning made it feasible that Nicola could be leader.”

In a political world where Boris Johnson gets stuck on a zip-wire, Treasury Minister Chloe Smith is mauled on Newsnight and U-turns are forced over a pasty tax, the writers’ biggest problem is staying ahead of events.

Tandy said: “There are things we say we couldn’t put in the script because no-one would believe it. Then Jeremy Hunt did his bell-ringing (where the bell flew off). And he’s still got a job. We get very lucky sometimes.”

At one point the writers feared that a script leak had been turned into Whitehall policy. The opening episode finds Mannion announcing the “silicon playground” – school children design apps for free, with the profits offset against future university tuition fees.

“Next day Michael Gove announced exactly the same policy,” complained Gray. The Education Secretary backed a cheap computer circuit board, the Raspberry Pi, which he wants children to use in schools to develop their programming skills. Drew said: “We thought ‘the fucker’s nicked our material’. There’s been a leak and they’ve decided to use material from our show.”

A judicial inquiry, sucking in ministers and advisers, provides the backdrop for the new series, although the subject is not phone-hacking. The promise of a 5-year Coalition allowed the team to “reboot” the series. Tandy said: “We’ve embraced wholeheartedly the fact that no-one won the election. Peter Mannion has to share his office with an upstart schoolboy.”

Roger Allam, who plays Mannion, said: “The Coalition means there’s even more conflict and less possibility of anyone being happy. No-one’s in real power.”

Will Smith, a series writer who plays Mannion’s adviser Phil Smith, said: “The Lib Dems are keen to show they can work harder and can be as tough as the larger party. We were hearing that the Coalition parties were getting on with each other and the tensions were actually within each party. Luckily for us by the time we filmed the series it was starting to come apart a bit more.”

Smith admits: “When Francis Maude told people to fill up the jerry cans in their garage, that was rather like a scene we would have done. It was so ludicrous that this could actually happen.”

Who’s who?

Fergus Williams (Junior Minister, DOSAC, Coalition) , played by Geoffrey Streatfeild

Upwardly-mobile “Lib Dem” arriviste complains when his “network nation” policy is mangled by “Tory” boss Mannion. Ministerial inspiration could include Steve Webb and Jeremy Browne.

Helen Hatley (Special adviser to Leader of the Opposition), played by Rebecca Gethings

Controlling influence over Nicola Murray, thwarting Malcolm Tucker. “More of a carer than an adviser”. Ed Miliband’s private office has included Polly Billington, Lucy Powell and Ayesha Hazarika. (nb- past tense, they have now quit)

Stewart Pearson (Director of Communications, Government), played by Vincent Franklin

Blue-sky thinker whose “touchy-feely” policies are sidelined in Downing Street as Coalition faces daily crises. Bears close comparison to Steve Hilton, David Cameron’s departed policy guru.

Malcolm Tucker (Media advisor, Opposition), played by Peter Capaldi

Muted in opposition, berates Murray for not being hungry enough for power. “You’ve got be a Hutu, hacking your way through the fucking opposition.” Former Times political journalist Tom Baldwin is Ed Miliband’s strategy chief.

Peter Mannion MP (Minister of DOSAC, Coalition government), played by Roger Allam

Old-school, lazy Tory, behind the curve on technology who confuses “silicon playground” policy with “Fibre-optic Fagins”. Allam calls him “a Ken Clarke who has never held the big offices of State”.

Glenn Cullen (Fourth sector guru, Government), played by James Smith & Olly Reeder (Special advisor to leader of the Opposition), played by Chris Addison