Environment ministers from more than 170 countries will meet from 14-23 February in Cartagena, Colombia, to finalise the text.
Observers say that crucial differences of opinion remain to be overcome.
Notable among these is the USA, the world's largest GM-crop producer, which has not signed the biodiversity convention. GM crop producers want to place the burden of regulation of GMOs, as set out by the protocol, onto importing countries rather than exporters. Developing countries are concerned that importing GM crops could threaten traditional farming methods and endanger biodiversity. According to one observer, many African and Asian countries are determined not to sign the protocol unless their demands for a strict liability mechanism and the right to refuse to import GMOs is granted. Another key unresolved issue is whether the protocol will cover only live GMOs or also GMO products such as vaccines, drugs, processed foods and food additives.