China and Russia signed $4 billion dollars' worth of trade deals on Tuesday during a visit by Chinese President Hu Jintao focused on upgrading their strategic partnership relations.

Chinese President Hu Jintao (R) shakes hands with Russian President Vladimir Putin (2nd L) as Russian First Deputy Prime Minister Dmitry Medvedev (L) and Chinese Deputy Prime Minister Wu Yi applaud after signing the guest book at a Chinese national exhibition in Moscow March 27, 2007. [Reuters]

Presidents Hu Jintao and Vladimir Putin oversaw the deals on the second day of Hu's visit to Russia.

"For Russia, China has always been one of the most important economic partners in the world, and throughout recent years our business ties have steadily grown and strengthened," Putin said, speaking at the opening of China's biggest-ever trade fair in a foreign country.

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The presidents oversaw the signing of 21 contracts, including an agreement by Russian state oil company Rosneft to supply jet fuel to China and long-term export contracts for Russian steel products. Among the biggest contracts was a 460-million-dollar agreement by Russia's Novolipetsk Steel to supply 94,000 tons of steel to Chinese electrical parts maker Tebian Electric Apparatus Stock from 2007-2011.

About 200 Chinese companies showcased their brand-new products at the fair, which Putin used to underline Russia's growing interest in developing its high-tech sector with Chinese help. "We are particularly interested in exhibitions devoted to innovative and information products, aviation, aeronautics and energy, the nuclear industry," Putin said.

Russian oil companies agreed to increase deliveries of crude and oil to China, whose booming economy and rising forex reserves have strengthened its buying power worldwide. The oil deliveries are expected to jump from the 11 million tons shipped in 2006 to 15 million tons per year, mainly by rail, Russian Railways head Vladimir Yakunin told reporters.

President Hu continues his trip Tuesday evening with a visit to Tatarstan, a mainly Muslim province in central Russia that has extensive oil reserves. He will meet there on Wednesday with the region's leader Mintimir Shaimiyev.

Other agreements were signed between Russian and Chinese banks and space agencies.

Hu and Putin also talked up diplomatic ties between their countries, which have taken closely aligned positions in talks meant to end North Korea's nuclear weapons program and stem Iran's nuclear plan.

In a joint declaration on Monday, the two presidents said the standoff over Iran's nuclear program "should be resolved exclusively in a peaceful way," and welcomed the "positive dynamic" in six-party talks aimed at curbing North Korea's nuclear program.