Russian President Vladimir Putin on Tuesday praised growing economic ties with "natural ally" Beijing as he hosted Chinese premier Li Keqiang for high-profile talks.

Li's three-day visit to Russia comes as the Kremlin is locked in a battle of wills with the West over Ukraine and is seeking to ramp up cooperation with Asia and Latin America.

"We are natural partners, natural allies, we are neighbours," Putin told Li during talks at the Kremlin.

"We are setting large-scale, absolutely realistic goals for ourselves and no doubt this will serve our peoples well," he added.

The Chinese prime minister for his part praised the "inexhaustible" potential for cooperation between China, the world's largest energy consumer, and Russia, one of the largest energy suppliers.

"We are witnessing a growing tendency of the development of our cooperation in all spheres," Li said.

Li and Putin spoke after Russian and Chinese officials on Monday signed dozens of deals ranging from energy to banking to cars.

The two countries agreed to open a yuan-ruble swap line worth 150 billion yuan ($24.5 billion) to reduce dependence on the US dollar and promote bilateral trade and investment.

"A large amount of agreements have been signed," Putin said in remarks released by the Kremlin.

"But it's not the quantity that matters. What's important is that they are promoting our real cooperation, and in very different fields, both in energy and hi-tech, which is especially important."

After a decade of tough negotiations, China and Russia inked a 30-year, $400-billion agreement in May that will eventually involve Moscow supplying Beijing with 38 billion cubic metres of gas annually.

Critics, however, claimed that in his bid to spite the West, Putin signed an agreement that was more beneficial to China than to Russia.

- Tiger diplomacy -

Ahead of Li's visit to Russia, the two countries got caught up in a diplomatic incident of sorts when an endangered Siberian tiger wandered over the border into China in search of a meal.

The big cat, named Kuzya, was among three Siberian tigers released into the wild by the Russian president in May.

Kuzya's arrival sparked fears that the rare animal could fall victim to Chinese poachers.

The foreign ministry in Beijing pledged that Putin's tiger would be protected, citing an existing agreement on cross-border protection of Siberian tigers.

"We will make joint efforts with the Russian side to protect wild Siberian tigers which travel back and forth between China and Russia," foreign ministry spokesman Hong Lei said in a statement.

Once bitter foes during the Cold War, Moscow and Beijing have over the past years ramped up cooperation, driven by a desire to counterbalance US global dominance.

China has spoken out against Western sanctions against Russia and has called on all sides to reach a political settlement over Ukraine.

Ahead of his Moscow visit, Li travelled to Germany for talks with Chancellor Angela Merkel. He will also participate in a Europe-Asia summit in Milan later this week.