Ed Miliband would be a 'catastrophe ' for Britain , according to FTSE 100 bosses . Seven out of 10 business chiefs at Britain 's biggest companies think Ed Miliband would be a 'catastrophe ' for Britain , a survey has revealed . The poll of FTSE 100 chairman has revealed overwhelming support for David Cameron to remain Prime Minister , despite the widespread business concern over his pledge to hold an in-out referendum on Europe . It comes just days after more than 100 company bosses signed a letter warning against a Labour government . It also echoes controversial remarks by the Boots chief executive Stefano Pessina who sparked fury after claiming it would be a 'catastrophe ' for the UK if Labour won the election . The poll of 35 business chairman , by the headhunters Korn Ferry , is a further blow to Labour which is struggling to repair its relationship with big business after a series of controversial policy announcements . Mr Miliband last week vowed to ban 90 per cent of zero-hours contracts and unveiled proposals to make it easier for workers to take their bosses to court for unfair dismissal . He also confirmed plans to raise corporation tax for the first time in 40 years to raise cash for a £400 cut in business rates for smaller firms . One of the FTSE 100 bosses surveyed , who did not want to be named , said businesses could work with Labour 's shadow business secretary Chuka Umunna and its economics chief Ed Balls . But he said Mr Miliband 's 'tone and rhetoric ' had proved 'deeply disturbing ' , adding : 'At times his language is vitriolic and he appears to completely misunderstand business . ' Mr Umunna , speaking on Radio 5 Live today , Umunna insisted Labour was no anti-business and defended Mr Miliband 's recent announcemtn that Labour would all-but outlaw zero-hours contracts . Mr Umunna admitted not all zero-hours contracts were 'awful and bad ' , but insisted many workers were being exploited . Scroll down for video . Mr Miliband has vowed to force companies to offer staff a full time contract if they have been working regular hours for three months . Mr Umunna said : ' I think this will be massively helpful . There are 1.8million zero hours contracts now and I think this will transform people 's lives . ' The shadow business secretary has also pointed to Labour 's refusal to offer a European referendum as a policy which business supported . David Cameron and George Osborne , out campaigning today , have jumped on business criticism of the Labour Party to boost their core campaign message that only the Tories can be trusted with the economy . He said : 'Business people have been very impressed that Ed took a decision on a matter of principle on the in-out referendum . It would have been easier to dance to Nigel Farage 's tune , as the Conservatives have done . ' Last week , Mr Umunna and a host of other Labour figures hit out at Britain 's top business leaders after they backed the Conservatives ' economic plan and urged voters not to risk a 'change of course ' . In a highly unusual intervention just weeks from the general election , the business chiefs claimed a Labour government would 'put the recovery at risk ' . Mr Miliband said the letter was not a surprise and only showed that the Tories were on the side of ' a few big firms and individuals at the top ' . Mr Umunna , meanwhile , dismissed the signatories as a 'cosy little club ' , while Labour peer John Precott went further criticising them as 'tax dodgers , Tory voters and non-doms ' . Mr Cameron , however , insisted the intervention was 'unprecedented ' and claimed it sent a 'very powerful message ' . The business chiefs who signed the letter run companies with well known retail brands such as Primark , Iceland , Ladbrokes and Costa Coffee . Bosses behind big name retailers , drinks and restaurants have backed the Tory economic plan , including ( top row ) Primark and Costa and ( bottom row ) Ladbrokes , Cobra , Tango and Iceland . Executives at consumer brands such as Cobra beer , Britvic , Silver Spoon , Kingsmill , Thorntons , Robinsons , Tango and London Pride are also on the list . Embarrassingly for Labour , the list of business chiefs includes several who supported the governments of Tony Blair and Gordon Brown . However , Mr Miliband said the letter only served to expose the choice at the election . He said : 'Businesses have come out today to say they want lower business taxes and , you know , that does n't surprise me . 'But it does also go to the wider choice at this election . The Conservatives really believe that if all of the few corporations and individuals at the top are doing well , the wealth will magically trickle down for everybody else . 'We have tried that experiment over the last few years and it has n't worked . We have seen falling living standards and falling wages and insecurity at work . I just have a different view about the way the country succeeds . '
Poll of FTSE Seven bosses reveals overwhelming support for the Tories . 100 out of 10 said Ed Miliband fearful of a Labour Government . Comes after Seven business chiefs signed an open letter in support of Tories . Mr Miliband said letter only showed PM backed his rich friends in the City .