Shadow Chief Secretary to the Treasury Pat McFadden said he had never seen a Chancellor "so comprehensively trash" his own Government by describing its record as a "vicious cycle of stagnation".
The Wolverhampton South East MP said the Government was "running a huge risk" by signing off on huge levels of borrowing to fund a raft of tax cuts that would "mostly benefit the wealthy".
Tax cuts were a key feature of a major shake up of public finances unveiled by Kwasi Kwarteng aimed at growing the UK economy.
Mr McFadden told the Star: "It was extraordinary to hear the Chancellor admit so clearly that the Conservatives have failed. Sometimes you expect a Chancellor to blame the previous Government.
"But I’ve never seen a Chancellor so comprehensively trash his own Government by describing its record as a 'vicious cycle of stagnation'.
"Growth is the right question and one we’ve been pointing out for some time. The question is whether these measures will produce it.
"The Government is running a huge risk with the public finances by borrowing so much to fund tax cuts that will mostly benefit the already wealthy."
He said the Treasury was now in a "tug of war" with the Bank of England. "Having borrowed so much for the sugar rush of tax cuts, ministers have put more pressure on the Bank to increase interest and mortgage rates even further, and that’s not going to help with economic growth or with household finances," Mr McFadden added.
“This is return to the discredited idea of trickle down economics that says if only we reward the already wealth, everyone will benefit.
“For that reason it felt more like back to the future than a brave new world.
"A real plan for growth would have put much more emphasis on investing in more energy security, equipping our workforce with the skills needed for the jobs of today and tomorrow, reforming business rates to help businesses and giving some institutional stability to investors in the UK."