Trade negotiators are gathering in the Chinese city of Dalian in the hope of restarting flagging world trade talks.
Support for farmers is the key issue in Dalian
The aim is to flesh out an outline deal announced in May, which could break a deadlock on agriculture tariffs.
Farming is the big sticking point for December's top-level World Trade Organization (WTO) summit in Hong Kong.
The Dalian talks involve the US, China and the European Union, as well as the G20 group of developing nations and big farming producers such as Australia.
Farming subsidies and tariffs have long been a key problem in trying to reach a new trade deal.
Deal on the table
The current round of talks started in Doha in 2001.
Dubbed the "Doha Development Round", they were meant to put the needs of developing countries at the centre of trade negotiations.
Poorer states and campaigners say that has not happened, and point to continuing huge support of farming by the US, the EU and Japan.
The May deal set out a possible compromise on a particularly problematic, if abstruse, part of the issue.
And the G8 meeting earlier in July produced a promise from the US and EU that the subsidies would go, albeit without a date for it to happen.
At the Dalian meeting, Chinese Trade Minister Bo Xilai said the deadline should be 2010, the same date mentioned at the G8 by UK Prime Minister Tony Blair as a possibility.
"We all have a lot of areas of commonality," he said.
"We're going to push actively to come up with agreements."
But the talks are already well past their original target for completion, and December's meeting is seen as a last chance to get back on track.
"Every hour must be made to count," said WTO Director-General Supachai Panitchpakdi, who steps down in favour of ex-EU Trade Commissioner Pascal Lamy in August.
The G20 states as well as big producers - Australia and Brazil, for instance - argue that there is still a long way to go.
Poorer states also say that the rich countries are still demanding too easy access to their own markets for goods and services.