Thailand's Prime Minister Srettha Thavisin on Tuesday said his new government will stimulate the economy from the grassroots up, with a digital wallet policy likely to have a ripple effect equivalent to 5% of gross domestic product next year.

Srettha championed his signature 560 billion baht ($15 billion) digital wallet plan, the key election platform of his populist Pheu Thai Party, as among a series of "high-impact, quick-win" policies his government will deploy to breathe life into an economy struggling with weak external demand.

The policy aims to transfer 10,000 baht ($269.47) to all Thai nationals over 16 to spend digitally within a few kilometres of their homes. The government has yet to detail how it will be rolled out or financed.

"This will inject around 16 billion dollars cashflow into the economy. This is projected to create a ripple effect of 57 billion dollars which is equivalent to 5% of GDP growth next year," the premier said in an address at a forum hosted by a local newspaper.

Srettha said his government aimed to attract investment in high-tech, high skill industries and seek more free trade agreements, including with the European Union.

He also said moves were afoot to diversify Thailand's energy sources to bring more renewables into the power mix, in addition to attracting sustainability-focused investment and passing legislation on emissions. ($1 = 37.1100 baht) (Reporting by Panu Wongcha-um; Writing by Martin Petty; Editing by Kanupriya Kapoor)