A global G20 task force is rethinking its initial approach which involved targeting the biggest funds, and could opt for a more intrusive method that would affect more funds by limiting their market activities during periods of turbulence, the sources told Reuters.

The G20 group of developed and developing nations is likely to press for adoption of "rapid timelines" by different countries for automatic sharing of information with a view to curb tax evasion.

The Financial Stability Board (FSB) said on Monday it would propose "robust" global rules for cryptocurrencies in October, following recent turmoil in markets that has highlighted the need to regulate the "speculative" sector.