This comes in light of what the bank calls 'unprecedented market events of this week', which compelled the US government to step in to rescue insurer group AIG, while opting to allow another, Lehman Brothers Holdings, to fail.

Citi, in the letter dated Sept 17, said its net exposure to Lehman and its subsidiaries is modest and is being managed in an orderly fashion. It also points out that its business in Singapore is financially strong and well capitalised.

Reiterating the bank's health in a media briefing on Friday, Citi country head Mr Jonathan Larsen said it is still hiring, despite being more prudent in expense management.

'We're continuing to hire in specific areas where we need specific talent and resources,' Mr Larsen said.

Singapore is a key hub for Citi in Asia with about 9,000 staff.