FNB says customers have withdrawn R97 million (£8.5 million) in the first six months since the service was introduced in March this year.

Customers logging in to the bank's Cellphone Banking menu on their mobile type in the amount they wish to withdraw and specify the account details. In return they receive a one-time temporary PIN code by SMS, which must be used within 30 minutes of receipt.

Ravesh Ramlakan, CEO of FNB Cellphone Banking Solutions attributes the success to "the safety and convenience" of mobile banking.

"In hindsight, with Cash Withdrawal there's no risk of card skimming, as the customer does not need to use their bank card at the ATM," he says.

In June, the bank reported soaring uptake of its mobile services across the continent, with year-on-year growth of 376% in Zambia, 277% in Botswana, 204% in Namibia and 473% in Swaziland.

Ramlakan says that three million of its seven million customers now bank by phone and that the FNB is pouring more of its research and development effort into the mobile platform. "There is no doubt that cardless solutions are the future of banking," he says.

The latest figures have been released as the bank debuts a new service called Pay2Cell that allows its account holders to make payments to other FNB account holders using only the recipient's mobile number. The service currently works only for FNB customer-to-customer transactions, but the bank wants to see it taken up inter-bank.

FNB CEO Michael Jordaan said in a tweet on Wednesday: "For once I would actually like our competitors to copy FNB's innovation so Pay2Cell can work across SA."