HSBC's structure was "not fit for purpose" two years ago but Europe's biggest bank is not too big or complex after a far-reaching restructuring and series of disposals, its chief executive said.

"Our structure was not fit for purpose in a modern world," Stuart Gulliver told lawmakers on a British banking inquiry on Wednesday, saying he had implemented the biggest organizational change in the bank's history when he took the helm in 2011.

HSBC was fined $1.9 billion in December, the largest ever paid by a bank, followed a U.S. investigation into its Mexican and U.S. operations that made scathing criticism of its anti-money-laundering systems. The bank admitted failures were partly due to its complex structure.

(Reporting by Steve Slater; Editing by Dan Lalor)