Ed Balls may have contributed to the failure of talks between Labour and the Liberal Democrats after the last election due to his "bad body language", according to a new film.
The shadow chancellor is portrayed entering into negotiations after the 2010 general election in Channel 4 political drama Coalition, set to air on March 26.
The film, which stars Sherlock's Mark Gatiss as Peter Mandelson and Ripper Street's Mark Dexter as David Cameron, gives an insight into the conversations that went on behind closed doors in the days after the election.
But writer James Graham claimed that interviews with the key orchestrators behind those pivotal few days showed that Ed Balls was "noticeably unhelpful" in the negotiations.
He said: "That has been confirmed, but obviously people's opinion differs as to what extent the Labour party were ill-prepared and to what extent their body language was unhelpful.
"A lot of the Lib Dems accused them of having a certain arrogance. But when I spoke to Mandelson and a lot of the Labour party aides like Stewart Wood, they don't believe at all that they were unhelpful or arrogant or aggressive.
"Our job was to represent the idea that from the Lib Dems perspective, people like Ed Balls were noticeably unhelpful."
The shadow chancellor, played by Nicholas Burns in the drama, is shown to be slouching, with his arms crossed during fraught discussions with Lib Dem aides.
But after a telling off from Gordon Brown, played by Ian Grieve, in which the Labour leader reprimands Mr Balls and Harriet Harman for "not sitting up straight", the Labour camp goes back in for round two of the negotiations with a tray of muffins.
Mr Balls says: "I'll show them bad body language."
:: Coalition will be broadcast on Channel 4 on Thursday March 26 at 9pm.