Chinese President Hu Jintao, one of the five leaders of fast-growing economies invited to join the Group of Eight summit discussions on Monday, urged G-8 leaders to work more closely with developing nations.

"In the world today, peace, development and cooperation are the call of the times," he told fellow world leaders.

But "the problems and challenges confronting human development have increased," he said, citing rising oil prices, trade protectionism, terrorism, environmental pollution, infectious disease and terrorism.

Hu said global energy security -- an issue demanding international cooperation -- is "crucial to ensuring the economic growth and people's livelihood of all countries and to maintaining peace and stability and promoting common development."

Brazilian President Luiz Inacio Lula da Silva focused on trade, telling G-8 leaders that the stalled Doha Round of trade talks is a "political crisis" that he blamed on a lack of leadership.

He urged world leaders to act decisively on talks on new rules aimed at breaking down trade barriers. Negotiators now have until mid-August to find agreement on the Doha Round launched in 2001 -- a process already two years behind schedule.

South African President Thabo Mbeki and leaders of the African Union spoke of the lack of access to education on the continent, particularly for girls and young women.

"Without stability in Africa, there will be no world peace," Hu said, urging more First World attention to stability and development in Africa.

Three of the five countries invited to join the G-8 -- Brazil, India and Mexico -- boast bigger economies than summit host Russia.

But Chancellor Angela Merkel, whose nation hosts the 2007 summit, said she saw no reason to expand the G-8 to include members with burgeoning economies.

She said Monday that poverty -- a topic some non-governmental agencies complained was inadequately addressed at St. Petersburg -- would be at the top of the agenda in Heiligendamm in 2007.

Also invited to the joint working session of the G-8 were the leaders of Kazakhstan and Congo, representing regional organizations; U.N. Secretary-General Kofi Annan; African Union chairman Denis Sassou-Nguesso; Mohamed ElBaradei, director-general of the International Atomic Energy Agency; Koichiro Matsuura of UNESCO; International Energy Agency director Claude Mandil; World Bank President Paul Wolfowitz; Pascal Lamy, director-general of the World Trade Organization; and the acting director-general of the World Health Organization, Anders Nordstrom.

At the close of the session they adopted a statement condemning the train bombings last week in India that killed more than 180 people.

"We are outraged by the barbaric terrorist acts" carried out in Bombay, they said, expressing a determination to "continue the fight against terrorism by all legitimate means.

"We are united with India in our resolve to intensify efforts to fight terrorism, which constitutes a threat to each of our country, as well as to international peace and security."