US banks are taking advantage of improving earnings and growing investor demand to raise billions of dollars in debt at historically low interest rates, a move that could boost the sector's profits in coming years.

The burst of fundraising in the US is in stark contrast to Europe where banks have struggled to issue debt as the eurozone crisis and worries about the financial industry have undermined market confidence.

The cheap finance locked in by big institutions such as JPMorgan Chase, US Bancorp, Goldman Sachs and Morgan Stanley in recent days marks a remarkable comeback for a sector that was shunned by investors during the financial crisis.

Less than two years after the government was forced to intervene to ease a dramatic credit crunch, US banks sold more than $7bn in debt last week – the largest weekly total since September 2009, says Dealogic.

US Bancorp, a Minneapolis-based lender, raised $1bn in five-year bonds at an interest rate of 2.45 per cent – one of the lowest ever paid by a bank.

Lower funding costs boost profits because they increase the margins earned by banks on their loans to consumers, companies and investors.

Wall Street executives say recent debt issues were triggered by “reverse inquiries” – informal approaches by fund managers seeking to raise their exposure to a sector they had largely avoided since the crisis.

“There is a bit of a food-fight among investors to get hold of paper from US banks,” an executive at a big bank said. “After leaving the sector alone for so long, there is renewed appetite.”