MUMBAI: State Bank chairman Arundhati Bhattacharya today said some level of protectionism is needed to safeguard national interest and also encourage entrepreneurs to build companies of global scale."I think in matters of real national importance if it is important for the government to ring-fence certain things, the government should do it, because at certain phases some amount of protectionism is necessary," the SBI chief told the Wharton India Economic Forum here this evening.Bhattacharya was responding to a query on whether the Chinese model of building protective walls to help homegrown business is a good idea. She did not elaborate more.Talking about demonetisation, she said the move has given a huge push to the digital economy."In our wallet (SBI Buddy), we were having downloads of 6,000-7,000 a day and this now averages at 17,000-18,000. Our transactions at PoS were around 95 crore per day, which has surged to 410 crore daily now, while the average daily wallet transaction is over 6 crore now from 1 crore," the chariman of the nation's largest bank said.Stating that digitisation can bring down cost of transactions, Bhattacharya, however, said it will happen over a period of time."It's definitely a case that if you are doing transaction, that require less human intervention, then obviously it is cheaper in nature and the cost advantage has to be passed on to the consumer. There is no two ways about it," she said.However, Bhattacharya was quick to add that she does not believe that the country can be a complete cashless society."I always say that we are going to be a less-cash society and I think this is a more reasonable goal," she said.