DES MOINES, the United States, Feb. 17 (Xinhua) -- Chinese Vice President Xi Jinping said here Thursday that China and the United States should enhance collaboration in science and technology, promote bilateral trade and strengthen information exchanges so as to further deepen agricultural cooperation.

Addressing the China-U.S. High Level Agricultural Symposium held in the capital of Iowa, Xi said cooperation and exchanges between China and the United States in agriculture have maintained good momentum in recent years, primarily because both nations are big agricultural countries and enjoy vast shared interests and ample room for cooperation in the area.

It is also because China has fully implemented its World Trade Organization (WTO) commitment in the past decade, and reduced its tariffs on agricultural products to one quarter of the world's average, said Xi, who is in a five-day official visit to the United States.

In the past 10 years, the average annual increase of China-U.S. agricultural trade exceeded 20 percent. Bilateral trade volumes on agricultural products surpassed 30 billion U.S. dollars in 2011, making China the biggest export market for U.S. agricultural products, the vice president said.

The rapid increase of China-U.S. trade in agricultural products not only benefits the peoples of both countries, but also has found appropriate export markets for high-quality agricultural products from both countries, Xi said.

Moreover, the two countries have attached great importance to agriculture, and have conducted smooth and effective dialogue and substantial cooperation under such mechanisms as the China-U.S. Strategic and Economic Dialogue, the China-U.S. Joint Commission on Commerce and Trade and the China-U.S. Joint Commission on Agriculture, he said.

On further deepening China-U.S. agricultural cooperation, Xi called on both countries to enhance cooperation in science and technology, and make all efforts to improve the efficiency of agricultural production and push for sustainable development of agriculture.

Besides, the two countries should step up economic and trade cooperation, create a fair and rational market environment and fully tap their potential for cooperation, he said.

Both sides should also strengthen coordination and communication on international hotspot issues regarding agriculture and share information with each other, Xi said.

In his speech, Xi also stressed the importance China places on supporting farmers and rural development, as well as on food security.

China has always attached great importance to food security to ensure sufficient food supplies for its 1.3 billion people, Xi said.

According to the U.S. Department of Agriculture (USDA), China became the top market for U.S. agricultural goods last year, purchasing 20 billion dollars' worth of U.S. agricultural exports.

The U.S. farm exports to China supported more than 160,000 American jobs last year across a variety of business sectors, according to the USDA.

U.S. Secretary of Agriculture Tom Vilsack said at the symposium that the two nations will have to work together to help feed a growing global population.

"We have the responsibility and opportunity to work together to address the causes of global hunger that affect more than 925 million people," he said.

Calling the symposium "a historic event," Vilsack said it is "a real opportunity to strengthen an already-vibrant cooperative relationship built on mutual benefits and mutual trust between our two great nations."

"The rapid development of China-U.S. agricultural cooperation and trade has provided tremendous benefits to the people of both countries. We want to continue building those cooperative relationships," Vilsack said.

Also on Thursday, Chinese Minister of Agriculture Han Changfu and Vilsack signed a Plan of Strategic Cooperation that will guide the two countries' agricultural relationship in the coming years.