Australia's five biggest banks have been put on notice that the competition watchdog will use new surveillance powers to ensure they don't pass on the new bank levy to customers or shareholders.
The Australian Competition & Consumer Commission (ACCC) will be able to summon bank chiefs for hearings under oath in addition to accessing internal reports and emails to track whether $6.2 billion dollar levy over four years is being absorbed.
While the regulator doesn't have the power to stop the banks from defying the government's order to pay the levy to help with budget repair, it's sending the a clear message to banks that their every move is being scrutinised.
ACCC chairman Rod Sims has kept an unusually low profile since budget night while forming a surveillance squad to monitor the inner workings of Commonwealth Bank, Westpac, National Australia Bank, ANZ and Macquarie Group.
Mr Sims told the ABC's AM program that watchdog will use its new powers to force greater transparency in banking competition with a particular focus on the new bank levy.
"Of course we don't have power to stop the banks from doing anything but I think the fact that we're looking will have an effect," Mr Sims said.
"But we'll not only get access to reports they do internally we'll have access to emails and other such things. We've got the ability to get them (bank executives) in to have compulsory hearings under oath."
The ACCC's bank squad will comprise about a dozen specialists assessing competition in the finance sector with the option of hiring in external consultants with insider banking experience.
However, Mr Sims confirmed the ACCC would not have the ability to place officials inside banks to turn up the surveillance heat.
Earlier this week, Treasurer Scott Morrison accused banks of using a "voodoo blackbox" to cloud the true cost of banking and how fees to customers are formulated.
But Mr Sims is confident the new powers provided to the ACCC in the budget will be enough to keep major banks honest.
"We have information gathering powers that give us access to their information explaining internally how they're doing what they're doing," Mr Sims told AM.
"That's information they'll have to provide because they have a hierarchy and various layers in the organisation. But that key starting point we have is access to that internal information."
Mr Sims rejected claims by major banks that the bank levy was a last minute decision made in the days leading up to budget night.
"We had plenty of notice. We were given a look at the potential direction and were able to comment on that. So we had all the notice one could expect," Mr Sims said.
But in the face of a fightback from the major banks, Rod Sims denies he is feeling the pressure from Scott Morrison to deliver on greater banking transparency.
"We're not in the pressure feeling business. We're pretty relaxed. We're asked to do a job and we'll do that job well."
The five major banks last night received confidential briefings on how the levy will work but were required to sign confidentiality agreements beforehand.
However, banks are expected to continue reporting to the stock exchange in the coming days on how the levy could impact future profits.