Bankers must be jailed for serious wrongdoing to help restore public confidence in the financial sector, Labour have said.
Chuka Umunna said it "cannot be right" that benefits cheats face being thrown in prison for low level misdemeanours while City workers rigging the system to make hundreds of thousands of pounds escape tough punishment.
In a speech on the future of financial services at Canary Wharf, the shadow business secretary insisted Labour was "pro-City" but "unapologetically critical" when necessary.
He said: "It goes without saying that politicians are not in a position to lecture on trust - we are less popular than you and we learnt the hard way after the expenses scandal, when we had to get our house in order.
"But at least the people saw politicians brought to book - with some of our number serving time in jail for their wrongdoing.
"Particularly in respect of the Libor rigging scandal, it seems to me that we will not rebuild trust with the public or affect a culture change in finance until custodial sentences are imposed on those guilty of criminal wrongdoing in your sector.
"It cannot be right that someone who seeks to cheat the benefits system out of a couple of hundred pounds in my constituency may well be thrown into jail for doing so, but those who seek to rig the financial system and receive hundreds of thousands of pounds as a result never seem to suffer the same fate.
"Is not the prospect of jail for gross wrongdoing one of the best ways we can affect a culture change?"
Mr Umunna also singled out Barclays for criticism, claiming its decision to announce bonuses worth £40 million as the Budget detailing the Government's continuing austerity measures was unveiled last month sent "all the wrong messages".
He added: "For us, the future of financial services - the City - is incredibly important. Any potential Government hoping to take office and any current party of opposition charged with scrutinising what the Government does, should want to see the City thrive."