Citigroup’s crisis intensified on Thursday as its shares dipped below $1 amid growing investor concerns over the US government’s decision to bail out the troubled bank by taking a stake of up to 36 per cent.

Citi’s shares, which peaked at more than $56 in 2006, fell to a low of $0.97 in morning trading in New York, before recovering to close at $1.02, down nearly 10 per cent. At that level, Citi’s market value is just $5.6bn.