Last few yards of TPP very difficult: Robb

Trade Minister Andrew Robb says even though countries negotiating the Trans-Pacific Partnership agreement are 95 per cent there, the "last few yards are very difficult".

Sugar and dairy were key sticking points when the free trade talks ended in Hawaii last month, as was the issue of motor vehicles between Mexico, the US, Canada and Japan.

"The closer we get to a US presidential election, the more prospect (there is) of it falling over," Mr Robb told the National Press Club in Canberra.