SINGAPORE, Aug 19 (Reuters) - Indonesia's biggest tech group GoTo is set to complete a pre-IPO funding exercise to raise up to $2 billion in the next few weeks, but regulatory delays threaten to push its listing plans to early next year, three sources familiar with the matter said.

The delay comes as the southeast Asian nation's Financial Services Authority (OJK) weighs new listing guidelines for tech firms to offer dual-class shares that confer different voting rights, said two of the sources.

All the sources sought anonymity as they were not authorised to speak to the media.

A spokeperson for GoTo declined comment while there was no immediate comment from the regulator, OJK.

GoTo, formed through the merger of ride-hailing-to-delivery-to-payments firm Gojek and e-commerce leader Tokopedia in May, was targeting to list in Indonesia by year-end, followed by a U.S. listing, with a potential valuation of about $40 billion.