The International Whaling Commission has approved measures designed to prevent past so-called cash for votes scandals from happening again.
The 89-nation body was rocked last year by published accusations that Japan used cash and development aid to buy votes.
Japan, which denied this, is one of three countries to continue commercial whaling despite a 1986 moratorium.
The new measures, proposed by Britain, will mean countries will have to pay membership fees by bank transfer from government accounts, enabling traceability.
Previously, delegates have been able to turn up and pay in cash.
Delegations will not be able to vote until fees have been paid.