About 30 trade ministers started discussions in the Swiss town of Davos on Saturday on the stalled Doha Round of global trade liberalization talks.

Participants in the gathering, which was held on the sidelines of the World Economic Forum annual meeting, include U.S. Trade Representative Susan Schwab, EU Trade Commissioner Peter Mandelson, Indian Commerce Minister Kamal Nath and Brazilian Foreign Minister Celso Amorim.

The four are considered to be the key players in the talks, representing both developed and developing members of the Geneva-based World Trade Organization (WTO).

The fate of the Doha Round hangs on the four WTO members bridging their differences on agriculture and industrial trade, which means the U.S. must offer further reduction on domestic farm subsidies, the EU must promise more agricultural tariff cuts and India and Brazil pledge more market access for industrial goods.

The five-year negotiations, aimed at helping poor countries development through fairer trade conditions, were suspended by WTO Director-General Pascal Lamy last July, after so-called last-ditch negotiations among key WTO members, which also include Australia and Japan, collapsed in Geneva.

Although technical work of the talks resumed in Geneva last November and private and informal contacts among WTO members have continued, there is still no clear sign that a breakthrough can be made, especially on agriculture issue.

Sources suggest that best outcome of the ministerial gathering in Davos, the first since last July, might be a so-called formal relaunching of the Doha Round.

But the relaunching seems meaningless if no substantial progress is made on agriculture and industrial trade.

Trade issue has been a focus of the five-day Davos forum, which opened on Wednesday with the participation of world CEOs and political leaders.

German Chancellor Angela Merkel, British Prime Minister Tony Blair, Brazilian President Luiz Inacio Lula and other figures at the forum have all called for concessions in the Doha Round.

"If it succeeds it will be great. If it fails it will be catastrophic," Blair told a session of the forum.

"If we want to give a signal to the poorest countries that they will have a chance in the 21th century, the United States, the United Kingdom, France and Germany must make concessions," Lula addressed a public meeting.