Traveloka, an Indonesian online travel startup, is in talks to raise a $400 million in a round led by Singapore’s sovereign wealth fund.

The funding round is expected to double its $2 billion valuation to $4.1 billion.

Proceeds from the latest financing round will be used to expand Traveloka’s business beyond airline tickets and hotel bookings to activities such as concerts and amusement parks.

Last year, Traveloka raised $350 million from Expedia and another $150 million from JD.com, East Ventures, Hillhouse Capital and Sequoia Capital.