The US government is in danger of missing its deadline of divesting all of its Citigroup shares by the year-end after a fall in stock market trading volumes prompted authorities to slow down sales in July and August.

The lull could prompt the US Treasury, which has a stake of about 17 per cent in Citi, to consider a share offering instead of selling the stock in small quantities in the market, according to bankers and analysts.

“The sales of Citigroup stock have slowed way down in July and August?...?The US Treasury will not finish its share sale by?...?the end of the year,” said Linus Wilson, a professor of finance at the University of Louisiana. “The only option for the Treasury if it wants to exit Citigroup before the year-end seems to be to conduct a large secondary offering of the stake.”