Mexico's Supreme Court is this week set to probe a case that could potentially force Citigroup, the troubled US bank, to sell its profitable and highly prized Mexican subsidiary.
A group of opposition senators has pointed out that the US government bail-out of Citi last year placed its Mexican subsidiary, Banamex, in breach of national law, which bans foreign governments from owning a stake in domestic banks.
For Citi, the case is of vital importance. Banamex is one of the brightest jewels in the group's damaged crown, and today accounts for roughly 15 per cent of global profits. By some estimates, it is thought to be worth at least $20bn.