Growing protectionist measures put in place since the 2008 global crisis have impacted 3 per cent of world trade, or about 500 billion dollars in trade, World Trade Organization (WTO) director-general Pascal Lamy warned on Thursday.

According to the WTO's latest G20 Report on Trade, released Thursday, new protectionist measures put in place over the past six months have affected 3 per cent of world trade, compared with 1 per cent previously.

The WTO has been monitoring the rise of protectionist measures, such as tariff increases, administrative measures at borders, local content requirements and anti-dumping measures since 2008.

"During the last six months protectionist pressures have intensified, but more worrisome, protectionist actions have intensified," Lamy told the opening session of the World Economic Forum on East Asia, being hosted this year by Bangkok.

The WTO chief likened the rise in protectionism to bad cholesterol.


"It's a slow accumulation of measures taken one by one, that after some time can clog up the arteries of the world economy," he said.

The WTO is pushing for a trade facilitating agreement at the next G20 meeting in Mexico, which would simplify and streamline customs procedures worldwide which now account for 10 per cent of the value of world trade.

Lamy said trade protectionism would have a serious impact on the fast-growing East Asian economies, which are "especially exposed to the vibrancy of trade," he said.

With Europe "seriously slowing down," the United States yet to address its problems and China slowing, Lamy suggested that regional governments concentrate on greater trade integration.

"The more they integrate, the more resilient they will be to external shocks that are going to be with us, I believe, for a long time," the WTO head said.