The Japanese Bankers Association will step up oversight of the country's benchmark interbank lending rates as part of global efforts to tighten supervision in the wake of the Libor rate-rigging scandal.

The association will revise rules for the Tokyo interbank offered rate, or Tibor, and put them in a code of conduct that banks must observe when they make submissions, it said in a statement on its website Friday. It's also considering measures such as setting up an independent oversight panel and requiring external audits, the group said.

Global regulators are attempting to repair or replace benchmark rates following the scandal that led to $2.5 billion in fines for UBS, Barclays and Royal Bank of Scotland Group. Japan's regulator has punished RBS, UBS and Citigroup for attempts to manipulate rates.