The lobby group, Environmental Investigation Agency, has called on China to stem its import of illegal timber from Indonesia's Papua province.
The agency's Sam Lawson, who is attending this week's UN Forum on Forests in New York, says most of the logs from Papua go to China and Beijing must to more to stop the illegal trade.
Mr Lawson co-authored the February report which uncovered the world's biggest smuggling racket involving a single type of wood.
A subsequent Indonesian crackdown on the trade saw hundreds of people arrested but, according to the Agency, failed to get key figures in the lucrative trade.
Mr Lawson says Indonesia and China's bilateral agreement to work to stop illegal logging has achieved little.
"China's economy has grown exponentially over the last few years and they're now by far and away the largest importer of illegal timber in the world as far as we can tell, and they're certainly the largest importer of illegal timber from Indonesia. So as a vital linchpin in the illegal timber chain, so far there's little we've seen in terms of response on the ground."
EIA's Sam Lawson