Indian Overseas Bank, Indian Bank, Syndicate Bank, Corporation Bank and Punjab & Sind Bank have not yet joined UPI, even though the government has been pushing for digital transactions. Digital payment platforms including Paytm, FreeCharge, MobiKwik, and RuPay, besides UPI App of several public, private, and foreign banks have witnessed significant surge in downloads as well as transactions, "They should come on board. I don't know why they have not yet joined," said A P Hota, Managing Director of National Payment Corporation of India (NPCI), which launched UPI. Thirty banks had already signed up with UPI, Hota added, including foreign banks like HSBC. It's aiming for one million transactions by the end-year. "UPI is the combined initiative of the banking industry in India and supported by the RBI. The demonetization period is a good time to push digital banking platforms like UPI. The government should ask five PSU banks to go for UPI," a banking source said.