The plan announced in August was a hybrid of two formulas for cutting tariffs, including a general reduction along with a sharper cut of the highest levels applied to certain products.

On Monday, the EU ambassador to the World Trade Organisation, Carlo Trojan, said Brussels would not insist on maintaining the formula in an intermediate agreement sought by the WTO's 147 member countries by the end of July.

"We are ready to try a different mix as long as we are comfortable with its contents," Trojan told colleagues during a general council meeting at the WTO headquarters in Geneva.

"We are prepared to work on an alternative project and await concrete propositions from the G20," he added in reference to a group of developing countries that includes Brazil, China and India.

The world trade body is heading into a burst of negotiations to conclude what is known as the Doha round of trade liberalisation talks by the end of the year.

The round, launched in the Qatari capital in 2001, stalled after ministerial level talks collapsed in September in Cancun, Mexico owing largely to disputes over government aid to farmers in rich countries.

At a meeting of 28 WTO trade ministers Thursday in Paris, the G20 and the Cairns Group of 17 agriculture exporting countries said they would work to come up with a new market-access formula.