US Trade Representative Susan Schwab said Joseph Glauber, an economist and expert in the field of international agricultural trade, would succeed Richard Crowder in the World Trade Organization talks.

Crowder, who was leaving his post on May 31 for personal reasons, has agreed to serve USTR as a consultant.

Glauber will step into Crowder's role as lead agriculture negotiator for the Doha Round. A deputy chief economist at the US Department of Agriculture since 1992, Glauber has worked in the Doha negotiations.

He also served as economic adviser at the so-called Blair House agreements leading to the completion of the Uruguay Round negotiations.

The Doha Round of negotiations, which was launched in 2001 but suspended in July 2006, has foundered in large part on farm disputes.

The four key WTO players -- the United States, the European Union, Brazil and India -- have pledged to redouble their efforts to reach their own agreement by mid-June. They are scheduled to meet in London on June 10, and hold another meeting between June 14 and 19 in a location as yet unannounced.