Colombo — Sri Lanka's central bank boss urged temples Wednesday to go hi-tech and accept electronic cash from worshippers as he blamed the custom of offering prayer money for a coin shortage.

Governor Nivard Cabraal told reporters the guardians of shrines in mainly Buddhist Sri Lanka should install a "tap-and-pray" system similar to the "tap-and-go" used for public transport in many nations.

"That way, God will also know who offered what," Cabraal said at a press conference, at which he also asked Sri Lankans to raid their piggy banks and put coins that they have stashed away back into circulation.

As part of the same drive, Cabraal said the central bank planned to send teams to collect coins that had been donated at religious sites in exchange for banknotes.

He was also negotiating with Hindu and Buddhist temples and Christian churches in neighbouring India to recover around 30 tonnes of Sri Lankan coins offered by visiting pilgrims.

Sri Lankan currency is not freely convertible in India. Sri Lankan coins are worthless for Indians unless they sell the coins for scrap metal.

Sri Lanka stands to save millions of dollars in mint charges if coins trapped in piggy banks and temples are freed up, officials said. (AFP)