* Chinese President Hu to visit St Petersburg Forum
* Russia seeks investment, China seeks energy
* Russia, China near deal on gas supplies
(Recasts, adds details)
By Thomas Grove
MOSCOW, May 6 Chinese President Hu Jintao will be the top guest at Russia's showcase investor forum next month as the Kremlin seeks to cement an alliance between the world's biggest energy producer and the fastest growing major economy.
Foreign Minister Sergei Lavrov said on Friday that Hu will meet Russian leaders and attend the St Petersburg International Economic Forum, which the Kremlin presents as Russia's answer to the annual World Economic Forum in the Swiss resort of Davos.
"We in the Russian Federation await the chairman of the People's Republic of China Hu Jintao, who will hold bilateral meetings and take part in the St Petersburg Economic Forum," Lavrov said at a briefing with Chinese counterpart Yang Jiechi.
Yang confirmed that Hu would travel to the St Petersburg forum, which Russian President Dmitry Medvedev is expected to open. It will run from June 16-18.
Russia and China, which had a border conflict in 1969, say their relations have never been better though some Russian officials express anxiety in private about China's growing clout and talks on energy sales have stalled in recent years.
But Russia, which is trying to stem capital outflows which totalled $38.3 billion last year, sees China as a potential source of billions of dollars in investment which Moscow says it needs to upgrade ageing Soviet infrastructure.
China has sought to secure long-term oil and gas supplies from Russia, though wrangling over gas prices has delayed the construction of a key gas pipeline to China that would allow the Kremlin to leverage its energy sales to European customers.
Russia's state-controlled gas company Gazprom (GAZP.MM) wants to pump 30 billion cubic metres of gas a year to China from end-2015 and a Chinese source said last month that a deal to end years of stalled talks could be reached by June.
Prime Minister Vladimir Putin has called for boosting sales of natural resources -- Russia's main exports -- to China, whose gas consumption is forecast to soar over the next decade.
But some senior Russian policy makers are concerned by the influence China wields over the global energy and commodity markets which drive the fortunes of Russia's $1.5 trillion economy, which is dwarfed by China's $5.9 trillion GDP.
China was Russia's single largest trading partner in 2010, accounting for 9.5 percent of Russia's external trade, though as a whole the European Union was vastly bigger, accounting for 49 percent of Russia's $625.4 billion external trade. (Writing by Guy Faulconbridge; editing by Steve Gutterman)