Brazil and the United States were among the chief negotiators unable to agree a deal at World Trade Organization talks last July, effectively bringing five years of global trade talks launched in Doha in 2001 grinding to a halt.

Schwab described the talks in New York Wednesday as "very constructive" and said both sides approached the negotiations in "a problem-solving rather than finger-pointing manner."

"More of these kinds of conversations really represents the best opportunity we have of finding a way to a successful outcome to the Doha round," she said. "We all know there's really tough bargaining ahead."

"The key lies in lots of quiet conversations at the ministerial level, the sub-ministerial level, in bilaterals, in small groups so as to make progress on a lot of the technical issues."

Amorim said both sides were interested in seeing a successful conclusion to the Doha round but that he was encouraged by his talks with Schwab.

"We are having a good start for the New Year with these talks."

"On both sides, we think it's doable. There's a lot of hard bargaining ahead I can tell you for sure, I confirmed that today. But I think it's in good spirits and always looking for a solution," he said.

Brazil heads the Group of 20 developing nations struggling to persuade developed states to end farm subsidies, and is one of the chief WTO negotiators along with the United States, the European Union, India, Japan and Australia.

Schwab and Amorim would meet again at the World Economic Forum in Davos, Switzerland, later this month.