Rumblings of war in the Middle East cast a shadow over the East Asia Economic Summit Sunday as government and corporate leaders met to map out a plan to revitalise growth and deflect a looming crisis.

Calls for unity in the face of adversity dominated the opening day of the three-day World Economic Forum (WEF) meeting, which is attended by some 800 participants from 33 countries.

Malaysia's International Trade and Industry Minister Rafidah Aziz said Asia should accelerate integration efforts to cushion the effects of a threatened US-Iraq war that would "wreak havoc" on the global economy, escalating oil prices and disrupting trade.

"Asian countries and Asian companies must strive to synergise to make Asia work for Asia. It may be inward-looking but there is no two-ways about it," Rafidah said.

Kenneth Courtis, Goldman Sachs vice-chairman for Asia, said the threat of war was dragging down Asian economies at a time when regional growth had broadly peaked.

There were increasing signs of deflation gathering momentum in the region, with rising debt levels, and weak confidence and slow investment in the corporate sector, he said.