Japan's actions may hold the key to the rescue of the Kyoto Protocol, according to a World Wide Fund for Nature climate change campaigner.

The protocol -- adopted at international climate change talks in Kyoto in December 1997 -- is a multilateral agreement to curb global warming.

When talks held in November fell just shy of cementing the pact, participants were optimistic they could bridge lingering gaps when negotiations reopen in Bonn in July at COP6, or the sixth Conference of Parties to the U.N. Framework Convention on Climate Change.