The giant Trans-Pacific Partnership trade talks are in danger of breaking up without agreement after the United States gave little ground on market access, withdrawing an offer it had previously made to Australia on dairy products.

Talks went late into the night on Friday and resumed early on Saturday as the closing press conference was postponed from 9.30 am Australian eastern time until midday with talk that it might be postponed again.

If there is no agreement, the Hawaii talks might be extended, or more likely postponed until late August.

The tight deadline is needed to get in ahead of the US presidential election season, in which it is believed nothing agreed between the 12 nations will be approved by the Congress. Canada is also due to hold an election in October.