SHANGHAI: Russian President Vladimir Putin, facing isolation in the West over Ukraine, received a diplomatic boost Tuesday on a state visit to China, where he hopes to extend his country's dealings with Asia.
Putin met with Chinese President Xi Jinping at the start of a two-day conference on Asian security with leaders from Iran and Central Asia.
The two governments are negotiating a multibillion-dollar sale of Russian gas to China, and officials have said a deal might be completed in time to be signed during Putin's visit.
The deal would give Moscow an economic and political win at a time when Washington and the European Union have imposed asset freezes and visa bans on dozens of Russian officials and several companies.
The U.S. treasury secretary, Jacob Lew, appealed to China during a visit last week to avoid taking steps that might offset the impact of sanctions. However, American officials have acknowledged China's pressing need for energy.
The deal to pipe Siberian gas to China's northeast would help Russia diversify export routes away from Europe. It would help to ease Chinese gas shortages and heavy reliance on coal.
Putin told Chinese reporters ahead of his visit that China-Russia cooperation had reached an all-time high.
"China is our reliable friend. To expand cooperation with China is undoubtedly Russia's diplomatic priority," Putin said, according to the official Xinhua News Agency.
Xi and Putin were scheduled to kick off a joint exercise between their two navies in the northern part of the East China Sea.
The two countries developed a strategic partnership after the 1991 Soviet collapse, including close political, economic and military ties in a shared aspiration to counter U.S. influence, especially in Central Asia.
Talks on the proposed 30-year contract between Russia's government-controlled Gazprom and state-owned China National Petroleum Corp. began more than a decade ago.
A tentative agreement signed in March 2013 calls for Gazprom to deliver 38 billion cubic meters of gas per year beginning in 2018, with an option to increase that to 60 billion cubic meters.
Plans call for building a pipeline to link China's northeast to a line that carries gas from western Siberia to the Pacific port of Vladivostok.
A gas deal would mean China would be in a "de facto alliance with Russia," said Vasily Kashin, a China expert at the Center for Analysis of Strategies and Technologies in Moscow.
In exchange, Moscow might lift restrictions on Chinese investment in Russia and on exports of military technology, Kashin said in an email.
"In the more distant future, full military alliance cannot be excluded," Kashin said.
"It will, however, take years for China to start playing in the Russian economy a role comparable to that of the EU," he said. "After that happens, both China and Russia will be much less vulnerable to any potential Western pressure and that, of course, will affect the foreign policy of both these countries."