But Professor Sachs said that even a tribunal with limited powers could succeed.

Professor Sachs said that Poland's economic problems and debt burden were huge.

Professor Sachs began his career as an innovative expert on international economics in the early 1980's.

Professor Sachs's prestige in academic circles suffered with time, too.

Its affiliates include only 10 or 20 economists, Professor Sachs estimated.

According to former colleagues, problems with Professor Sachs's management style, rather than these events, led to his departure.

Professor Sachs's hiring, he said, was meant to bridge the gap between the social and natural sciences.

In addition, he said, Professor Sachs brings enormous energy to the job.

"It is an attempt to do something other than push official money into these crises," Professor Sachs said.

"There is no way these diseases can be addressed without international assistance," Professor Sachs said in an interview.