China's new leader Xi Jinping said Saturday his first foreign trip as president to Russia had exceeded his expectations and hailed the strong partnership between the two countries after signing numerous energy deals.

"I can say that from my point of view, my visit has already achieved its aim and the results have already far exceeded my expectations," Xi told Russian Prime Minister Dmitry Medvedev in comments translated into Russian and posted on the Russian government website.

The Chinese president met Medvedev at his suburban residence Saturday, a day after holding talks with his Russian counterpart Vladimir Putin and overseeing the signing of a raft of energy and other agreements as part of a three-day visit ending Sunday morning.

His trip came after China this month completed a power handover which will see Xi preside over the world's second-largest economy for the next decade.

Smiling and wearing a bright red tie, Xi told Medvedev he was "very satisfied with the results" of the visit on the last full day of his trip to Russia, the first step on a tour that will then take him to Africa.

The Chinese leader, who travelled to Russia along with much-watched first lady Peng Liyuan, told Medvedev that his choice of Russia for his first foreign visit was "in order to show this importance, this special character of our relations."

Xi said Friday that he and Putin had agreed on a deal that will see Russia, the world's largest energy producer, increase oil supplies to China, the world's biggest energy consumer.

"We can already say this is a historic visit with positive results," Putin said after he and Xi presided over the signing of an agreement between Russian oil company Rosneft and China's state-owned CNPC.

Rosneft chief Igor Sechin said the agreement would see Russia gradually raise oil supplies over the next 25 years from their current level of 15 million tonnes. At their peak the supplies are tipped to increase by 31 million tonnes a year.

As part of the deal, Rosneft is to receive a $2-billion (1.5-billion-euro) loan from China, he said, noting that a finalised accord would be signed at a later stage.

Russia's natural gas giant Gazprom also signed a preliminary agreement paving the way for a future 30-year contract that would see Russia begin sending gas to China in 2018.

Gazprom chief Alexei Miller said a legally binding document would be signed in June and the company expected to sign a final contract by the end of this year.

Also on Friday Russian Deputy Prime Minister Dmitry Rogozin and his Chinese counterpart Wang Yang oversaw the signing of agreements including a $2-billion deal to develop coal resources in Russia's Far East.

Medvedev said Saturday that the two sides had signed more than 30 documents in what he called "a very significant contribution to developing our relations."

Xi also hailed Russian-Chinese close relations as a guarantee of international peace during a televised speech on Saturday.

"Chinese and Russian relations are some of the most important bilateral relations in the world. Our relations are the best among the bilateral relations between great powers," he told students at the prestigious Moscow State Institute of International Relations.

"We must always be kind neighbours, good friends and reliable partners," he said in comments translated into Russian.

Once bitter foes during the Cold War, Moscow and Beijing have boosted cooperation in recent years to counterbalance US global dominance.

At the UN Security Council, China and Russia have both vetoed resolutions to impose sanctions on Syrian President Bashar al-Assad's regime, which is locked in a bloody two-year conflict with opposition rebels.

In a packed schedule, Xi began Saturday by meeting the speaker of Russia's lower house of parliament, Sergei Naryshkin, a top Putin ally, before meeting Russian Defence Minister Sergei Shoigou.

The two politicians "were in complete agreement" on international security issues, Deputy Defence Minister Anatoly Antonov told the Ria-Novosti state news agency after the meeting.

The Chinese premier also became the first foreign leader to visit the control centre for the Russian armed forces.

Xi was due to meet China experts on Saturday evening before flying to Africa on Sunday morning to shore up his resource-hungry country's soaring influence on the continent, first visiting Tanzania and then South Africa and Congo-Brazzaville.

Russia and China are members of the BRICS grouping of emerging economies, which also includes Brazil, India and South Africa and which will hold a summit in South Africa next week attended by both Putin and Xi.