By Alex Stevenson Follow @alex__stevenson
Ed Miliband is launching a fresh offensive against George Osborne, following the chancellor's defence of big bonuses for City bosses.
The Labour leader will call Mr Osborne "the last bastion of an old mindset" in a speech at Sheffield University later today.
Yesterday Mr Osborne insisted that the backlash against executive pay and bonuses was "anti-business" and needed to be resisted.
Last month he had defended RBS chief executive Stephen Hester's £1 million bonus, saying it could have been "worse for the taxpayer".
Those comments are prompting a major attack from Mr Miliband today, whose speech this evening will lambast the chancellor for "letting down British families".
"It is pro-business to demand responsibility at the top and an end to the something-for-nothing culture which has damaged our economy in the financial crisis at every level, wrecked businesses and left everyone else squeezed," he is expected to say.
"George Osborne has failed to give business the certainty it needs by bringing in a clear set of rules for an economy in which responsibility is hard wired in from the benefits office to the boardroom.
"Instead, he and David Cameron have intervened haphazardly and belatedly on bonuses while showing they are wedded to an old set of rules which are bad for people in the squeezed middle, bad for business, and bad for our economy."
Mr Osborne insisted he wanted to condemn rewards for failure in his speech to the Federation of Small Businesses earlier this week.
But he appeared to voice concern at the growing momentum of criticism of high rewards for already-well-paid executives. Earlier this week Network Rail's board agreed to forego its bonuses, blocking a £340,000 payout for chief executive David Higgins.
"There are those who are trying to create an anti-business culture in Britain - and we have to stop them," Mr Osborne said.
"At stake are not pay packages for a few but jobs and prosperity for the many."
Mr Miliband is using this defence to blame the government for not moving decisively enough to reform the bonuses culture.
His speech today attacks Mr Osborne and David Cameron of having intervened "haphazardly and belatedly on bonuses while showing they are wedded to an old set of rules which are bad for people in the squeezed middle, bad for business, and bad for our economy".
The leader of the opposition will add: "George Osborne and David Cameron have presided over a failing economy in which growth is flatlining and unemployment soaring.
"To claim they are champions of British business in such circumstances shows they are dangerously out of touch."