UN Secretary-General Ban Ki-moon is deeply saddened by the loss of lives in the flooding that hit Bangladesh's second-largest city on Monday, a UN spokesperson said Tuesday.

"The secretary-general is deeply saddened by the loss of over 100 lives, injuries of over 100 people, destruction and loss of livelihoods caused by the landslide and flooding that hit Chittagong City, the second-largest city in Bangladesh," the spokesperson said in a statement.

"He extends his deepest condolences to the families of those who have been killed or injured in the disaster," said the statement, adding "the United Nations stands ready to assist as required."