With an April 30 deadline fast approaching for agreement on key parts of a new round by the 149 country World Trade Organization (WTO), top negotiators from the European Union, the United States, Brazil, India, Japan and Australia met in London.

EU Trade Commissioner Peter Mandelson said the meeting had begun "in a business-like manner with a good atmosphere." But he played down any expectations of a breakthrough, saying the discussions were simply a further step in the negotiations.

"Our job is to build consensus in order to help the wider membership of the WTO to reach agreement later on," he said.

The WTO’s Doha round was launched in the wake of the Sept. 11 attacks on the United States as a way of giving the global economy a boost and spurring development in some of the world’s poorest countries.

But wrangling between the EU and the United States, developed and developing countries and also between poor countries has combined to slow the talks.

Indian Commerce and Industry Minister Kamal Nath, arriving for Friday’s start of talks, said the United States and the EU had to give poor countries more access to their markets and eliminate the "aberrations" of agricultural subsidies.

But Brussels and Washington are holding out for access to fast-growing markets in industrial goods and services in big developing countries, chief among them India and Brazil, in return for concesssions in agriculture.

Mandelson reiterated Europe was prepared to go further with its offer, but only if it gets what it wants in return.

"We’ve all put our offers on the table. No doubt we might and could and should revisit these offers if there is a good enough incentive to do so. That requires more on the table," he told CNBC television.

Mandelson has to contend with opposition from some EU member states to more concessions, however — chiefly France, which is the most vocal defender of Europe’s high farm import tariffs.

The US administration must also deal with a politically influential domestic farm lobby keen to defend subsidies.

Brazilian Foreign Minister Celso Amorim said it was important that negotiators did not let slip the April 30 deadline for agreeing the main details of how to free up trade in agriculture and manufactured goods in the round.