East Asia's three top industrial powers, all heavily dependent on imports of Middle East oil, have moved quickly to try to secure their supplies as the West tightens sanctions on Iran over its nuclear program.

China, Japan and South Korea sent ministers to Arab oil-exporting neighbors of Iran earlier this month to check whether alternative supplies to fuel their economies and transport systems would be available in case Iranian oil sales are curtailed. China's Premier Wen Jiabao was the latest diplomatic visitor to the Persian Gulf, traveling to Saudi Arabia, Qatar and the United Arab Emirates from Jan. 14 to 19.

The visits are part of a new attempt by leading Asian economies to balance their need for energy security with growing pressure from the United States and the European Union for more effective steps to deter what they suspect is Iran's covert program to acquire nuclear weapons capability — a development that could cause a dangerous arms race and instability in the gulf.