Under the plan, China, South Korea, Turkey and Mexico will all see immediate increases in their fund quotas to reflect the shifting balance of power in the global economy, he told reporters in an online briefing.
The quotas determine how much a member contributes to the International Monetary Fund, its voting rights and access to financing.
The plan will now be submitted to the IMF governors from each member country, who have the final say, and is expected to be approved in time for the global body's annual meeting later this month in Singapore.
"At present I think that all members recognise that relevant quotas and voting shares do not adequate respond to the reality of the world economy," said Rato, speaking from Washington late Thursday.
The changes aim to correct one-third of the current misalignment, he said.
Despite its newfound status as the workshop to the world, China has less voting power at the IMF than Belgium and the Netherlands combined.
The fund remains dominated by