Bank of Queensland has called on the government to consider whether Australia's big four banks are "too big to fail", as part of its inquiry into the financial system.
It marks another attack on the big banks' dominance by regional lenders, who say regulation favours the majors.
Chief executive Stuart Grimshaw told shareholders at the annual meeting on Wednesday that as the need for regulatory compliance increased, the costs were falling disproportionately on smaller players.
"A related issue that is increasingly occupying the minds of regulators here in Australia and overseas is that the inquiry must address the issue of banks being too big to fail," he said.
"In Australia, the reality is that the funding advantage that the banks currently enjoy creates incentives to become bigger and more complex."
Last week, the government released draft terms of reference and a proposed timetable of the inquiry.
Mr Grimshaw said the inquiry should tackle the differing capital requirements for big and small banks.
"As the banking system becomes more concentrated and complex, that further increases the financial stability risks," he said.
BoQ has been forced to reassure the owner-managers of its branches that it is committed to honouring franchise agreements after revelations it used police and security guards to block owner-managers from entering a Geelong West branch.
A Victorian Supreme Court judge criticised the decision, calling it a "retrograde step".
"The issues are specific to this particular branch and its owners," a BoQ spokesman told BusinessDay.
"We remain absolutely committed to our owner-manager network."
On Wednesday, BoQ warned of slower economic growth in 2014. It returned to profitability last financial year after being the first bank to make a loss in 20 years in 2012.
BoQ reported cash earnings to $119.9 million in 2013.