World Trade Organization talks in Geneva have failed to find agreement after the US said the European Union (EU) was not making enough concessions.
Rob Portman says the EU has not moved far enough
Trade ministers had spent three days trying to secure the framework for a new global free trade agreement intended to be put in place in 2006.
The US and EU have so far failed to agree cuts to food import tariffs and subsidies for their own farmers.
America's Rob Portman said the EU was proposing "insufficient" reductions.
Mr Portman on Monday said the US was prepared to cut its farm subsidies by 60% - but only if the EU and Japan reduced theirs by 80%, saying theirs were currently higher.
Peter Mandelson is leading the EU team
He also pledged that the US would lower its import food tariffs by up to 90%.
EU Trade Commissioner Peter Mandelson has now reportedly proposed farm produce import tariff cuts of only 24.5% on average.
"I don't think anybody considers that adequate," said Mr Portman.
Trade ministers have agreed to return to Switzerland for additional discussions next week.
The so-called Doha round of trade talks started in 2001, but has repeatedly stalled since then, primarily over disagreements on agricultural tariffs and subsidies.
In addition to arguments between the US and EU, there has also been disagreement between the wealthy nations and the poorer ones.
While the richer countries agree they need to reduce their trade barriers, they fear that making too many reductions could see them flooded with low-cost overseas goods that hit domestic jobs.
For this reason they also want developing nations to make concessions, something the poorer countries have so far resisted.
Trade ministers hope to have a framework global trade agreement in place ahead of the key WTO conference in Hong Kong in December.
This is timetabled to rubber-stamp the final deal.