The Commonwealth Bank of Australia (CBA) has joined in the fray of the escalating bank war in the country as it announced on Friday that customers switching from the National Bank of Australia (NAB) to them are poised to benefit from cash incentives and discounts.

It was in effect, CBA turning the cards on NAB, which earlier had made attempts of luring clients away from the former when it advertised this week that it is ready to shoulder mortgage exit fees so long as customers ditch CBA and pick them as new loan provider.

Now it's CBA's turn to seduce NAB clients as the bank announced that up to $1200 worth of cash incentives await those who wish their loans to be refinanced by CBA.

Also, NAB customers who wish to sign up for a credit card or deposit account with CBA will get their $100 cash incentives once they make the switch.

The latest move from the major bank is a clear answer to NAB's initial ploy of chipping away customers from its clients' base by offering hefty cash bonuses and discounts.

That move by NAB went further when it announced immediately the next day that it was severing its ties with Australia's other major banks, citing that it does approve the way that these banks are treating their clients.

Westpac did not take the ploy sitting down and moved swiftly to arrest the eating up of its market share by telling clients that some of its major entry fess would become a thing of the past and substantial discounts would be offered to customers who would avail of new mortgages with them.

However, industry observers said that CBA may have gained an edge by going the extra mile and dangling its cash incentives scheme.

According to its internal memo, CBA wants to underscore its distinction from its three rivals by providing "an incentive for NAB customers switching into one of our home loan, credit card or transaction products."

Also, CBA stressed that it specifically wants "NAB customers to experience our difference and the exceptional customer service that is available only through dealing with the Commonwealth Bank."