Former Labour leadership candidate Diane Abbott has warned Ed Miliband he will be a one term prime minister if he largely copies the Conservative's economic plan.
The Hackney MP said Labour had made a mistake by accepting the coalition's argument that there needed to be further spending cuts. And she singled out Ed Balls for direct criticism.
"Balls has a plan. He just does not feel able to spell it out to party members. It is called embracing Tory austerity," she said.
Writing in The Guardian today, the veteran Labour MP said the party would be doomed to be a one term government if it embraced the coalition's economic plan.
"If we accept the coalition cuts agenda, there will be another £25bn worth of public spending cuts needed after the 2015 election. They will be the deepest since 1948. It is difficult to see how a Labour government that implemented cuts on that scale could last more than one term," she said.
"So the urgency of framing an alternative to coalition austerity is not just about one month's polls. It is about the long-term survival of an incoming Labour government. And, even more important, challenging austerity is vital for the long-term life chances of communities and children yet unborn."
Abbott's attack mirrors that made by union leader Len McCluskey, who said recently that Labour would lose the 2015 election if all it offered was a "pale shade of austerity".
On Wednesday figures showed average pay rises have outstripped CPI inflation for the first time in four years. In a boost for David Cameron and George Osborne, other figures also showed continuing falls in unemployment and numbers claiming jobseeker's allowance as well as a record 30.3 million people in work.