EU and US trade negotiators meeting in Paris have struggled to reach final agreement on a global trade accord.
US trade chief Mr Zoellick says time is being wasted
Problems over farm subsidies threatened to undermine a global framework on trade which must meet a World Trade Organisation deadline.
The WTO wants an agreement between its 147 members for cutting import tariffs by the end of July.
Key delegates to the talks included US Trade Representative Robert Zoellick and European commissioner Pascal Lamy.
"There is some convergence on various points. At the same time, I would caution that there is still a considerable way to go," Robert Zoellick told reporters after the talks.
It was an informal meeting hosted by the Brazilian embassy that included trade representatives from the US, Australia, Brazil and the European Union.
The European Union was pushing at this meeting for the US to abolish export credits on farm goods.
These help US farmers to sell their goods overseas by offering low-risk loans to customers.
Washington has so far refused give much ground on this matter and accuses the Europeans of foot-dragging over proposed cuts to industrial aid.
The arguments drag on, and unless the framework is agreed this month, the so-called Doha round of trade talks could be held up for some considerable time.
If an agreement is reached by the end of July, it will be half way to a full accord on liberalising global trade in agriculture, services and industrial goods.
Agriculture is one of the main sticking points and was largely responsible for bringing the Cancun WTO meeting last September to an inconclusive end.
A US presidential election and possible changes at the top of the European Commission could cause further delays.
But WTO members agree the global economy needs a new treaty to cut tariffs and subsidies which would open up markets to more international business.