Leaders of Bangladesh, Bhutan, India, the Maldives, Nepal, Pakistan and Sri Lanka observed one minute of silence to kick off the 13th summit of the South Asian Association for Regional Cooperation (SAARC).

"These (disasters) have taken a huge toll in terms of lives and property and our heart goes out to the victims," Bangladesh Prime Minister Khaleda Zia said in an inaugural address.

The summit marks the 20th anniversary of SAARC's creation in Dhaka in 1985.

The grouping was formed amid much optimism to forge economic solidarity and boost living standards among the region's 1.4 billion people.

South Asia is home to half the world's poor, with 40 percent living on less than a dollar a day, according to the World Bank.

Zia said member countries must renew their efforts to improve living standards in the region.

"(We) must join the Asian mainstream of economic growth, prosperity and development," she added.