Developing countries led by India and Brazil are set on a collision course with Washington by stepping up their campaign in the World Trade Organisation to oblige patent applicants to disclose the origin of inventions using biological resources or traditional knowledge.

India, Brazil, Tanzania, Thailand, Peru and Pakistan last week proposed an amendment to the WTO’s intellectual property agreement that would make such disclosure a condition of receiving the patent. In the event of failure to comply, existing patents would be revoked or made unenforceable.