Efforts to put a value on greenhouse- gas emissions to contain global warming are being hurt as countries from Australia to Russia and Japan pull back from carbon-reduction commitments, according to the World Bank.

"While some nations are taking concrete steps forward on carbon pricing, recent developments in others are a setback," the World Bank said in its State & Trends of Carbon Pricing 2014 report published on Wednesday. Policy changes amount to "two steps forward, one step back," it said.

Carbon curbs need heavy lifting by all countries. Credit:Bloomberg

Greenhouse-gas emissions covered by pricing mechanisms such as taxes and trading programs may fall to 12 per cent from 18 per cent if countries including Ukraine and Kazakhstan don't ratify an extension of the 1997 Kyoto climate accord, the bank said. Russia, Japan and New Zealand renounced the emission- reduction pact's second commitment period covering the eight years through 2020.

Carbon pricing is needed to boost private-sector investment in clean energy projects at a time when public funding is limited, the World Bank said in its report. Forty countries and more than 20 sub-national jurisdictions have put a price on carbon, according to the lender.