Trade Minister Andrew Robb has hosed down fears the price of medicines will skyrocket with the signing of what has been dubbed the world's largest free trade deal, saying it is "not the intention or the outcome".

Mr Robb lashed out at consumer groups and the Greens for spreading misinformation about the Trans-Pacific Partnership, before walking into a meeting with 11 trade counterparts in Sydney on Saturday to finalise the "basic elements" of the deal.

Trade Minister Andrew Robb speaks during the Trans-Pacific Partnership meeting of trade representatives in Sydney. Credit:Reuters

"Those who are opposed to this scheme for all sorts of reasons are peddling a lot of misinformation, saying pharmacy costs will go up," he said on ABC Radio.

"This is not the intention or the outcome that will occur with this particular 21st century agreement."