For any other aborted business trip, it would be a reasonable request. But Bank of America has been obliged to apologise for asking 23 staff to refund fares for the US Airways flight which splash-landed in New York's Hudson River.

The bank's employees were travelling to the firm's corporate headquarters in Charlotte, North Carolina, when US ­Airways flight 1549 dramatically ditched off Manhattan last month.

In freezing temperatures, passengers were obliged to clamber onto semi-submerged wings and await rescue by ferry boats.

In the hours following the accident, Bank of America won praise for its response. It helped supply dry clothes, swiftly arranged alternative transport home for its employees and even organised a locksmith for those who had left keys in abandoned luggage.

But a day or so later, the bank stained its copybook by emailing those involved and asking them to pay back their fares on the grounds that their business travel had been cancelled.

A Bank of America spokesman blamed mid-level employees for following standard procedure for cancelled trips.

"In this case, there was no expectation that they would have to return the money," the bank told the Charlotte Observer. "We apologised to them. The bank is very sorry about this misunderstanding."

All passengers on the flight were sent two cheques by US Airways - one for $5,000 to cover any immediate expenses and a second to return the cost of their tickets.

The aircraft's crew were awarded ceremonial keys to the city of New York and captain Chesley Sullenberger has been praised as a hero for his airmanship in landing the stricken plane in one piece, allowing all 155 people on board to escape.

Several of the Bank of America staff on the flight were forgiving over their employer's demand for a refund.

"I was completely cool with it," Bank of America passenger Pam Seagle told US reporters. "It wasn't my money to begin with."