The Arab region is the only one in the world whose economy is shrinking, the head of the UN Development Programme (UNDP) told Saturday's An-Nahar daily.
Mark Malloch Brown told the Arabic-language newspaper during a visit here that while other developing regions may stagnate, the Arab world is the only to actually be regressing.
He did not give specific figures.
Malloch Brown also called on Arab countries to be more open to political reforms - including more democracy - if they wanted to halt this slide.
He said some Arab leaders were afraid to open up their countries to the outside world.
However, he agreed that such reforms must come from inside Arab countries and cannot be imposed by foreign powers.
The United States notably has plans for its so-called Greater Middle East Initiative which it says is intended to encourage democratic reform and economic opening in the Arab world and other Muslim countries.
However, a number of Arab states have expressed concern the policy will interfere in their internal affairs.