Japan, the world's fourth-largest buyer of timber products, needs to introduce laws and stricter oversight to stamp out imports of illegally logged wood, according to the activist group Environmental Investigation Agency.

The country's laws do not require private buyers of foreign timber to ensure it was legally logged nor do they provide for penalties for failing to do so, the Washington- and London-based group said in a report this week.

This has led to illegally cut wood in Russia being exported to Japan via Chinese processing plants, the EIA said.