Leaders representing 21 Asia-Pacific economies, meeting in the eastern Russian port city of Vladivostok, are focussing on food security on the second day of their conference. Discussions Saturday looked at ways to enhance global growth by tearing down barriers to trade.

Russian President Vladimir Putin called food security one of the most acute problems today as he opened the final day of talks at the Asia-Pacific Economic Cooperation summit, where bilateral meetings on the sidelines are nearly as important as group events.

On Sunday U.S. Secretary of State Hillary Clinton spoke with Malaysia's Prime Minister Najib Razak on the situation in Burma – particularly the unrest in Rakhine state, and territorial issues concerning a number of areas in the South China Sea.

She also met South Korean President Lee Myung-bak to review efforts to get North Korea's new leader to address nuclear concerns, and the need to calm tensions in the East China Sea.

The East China Sea also figured largely in Secretary Clinton's talks with Taiwan representative Lien Chan. The two also discussed the reopening of Taiwan's market to U.S. beef, and other economic and trade issues.

Mr. Putin is using the summit to promote Russia's ambitions to enhance its transport infrastructure across the two continents it straddles, bolstering exports to east Asia as demand in Europe wanes.

Chinese President Hu Jintao announced Saturday that his country also plans to boost its infrastructure, spending more than $150 billion on roads, railroads, and energy projects. He said enhancing his country's transport networks will enable China to import an extra $10 trillion worth of foreign goods in the next three years. Mr. Hu said strengthening infrastructure development is key to achieving economic growth.

On the sidelines, officials from Japan and Gazprom, Russia's gas giant, signed a preliminary agreement on construction near Vladivostok of a $13 billion natural gas plant and shipping port.

South Korea's Yonhap news agency says South Korean President Lee Myung-bak met with China's President Hu to express sympathy for a pair of earthquakes that hit southwest China Friday.

And U.S. Secretary of State Clinton and Russian Foreign Minister Sergei Lavrov signed a pact to enhance U.S. – Russia scientific cooperation in the Antarctic.

While in Russia, Clinton is also expected to meet with Mr. Putin to discuss how to stop the bloodshed in Syria, where government forces are fighting an 18-month battle against rebels.

The 21-member APEC forum accounts for 40 percent of the world's population, 54 percent of economic output and 44 percent of trade.