Modi and Putin met on the third leg of the Indian leader's four-nation tour of Europe with the pair looking to bolster declining trade between the once key partners.

The Indian premier is the guest of honour at this year's three-day Saint Petersburg Economic Forum - which is Russia's answer to the World Economic Forum held in Davos, Switzerland.

Speaking to journalists as the showcase kicked off, the Russian leader insisted that measures against Moscow, including economic sanctions over the crisis in Ukraine, had ended up having "zero effect."

Putin denies Russian culpability in US crisis

Putin suggested "patriotic" Russian citizens might be engaged in hacking, joining "the justified fight against those speaking ill of Russia," he said, adding that this activity was "never" carried out at the government level.

In March, the FBI confirmed that it has been investigating allegations of Russian interference.

Putin pointed out that it would be possible for it to look as if Russia were the source and denied again that his administration hacked the US election last year.

He said he hoped "Russophobia" in the West would "not last for too long, not forever, if only because the understanding has to come that it is counterproductive and harms everyone."

Putin also said on Thursday that "some Russians" may have acted on their own without their government's involvement in any hacking of the US presidential election in 2016..

Reviving an old friendship

For the Kremlin, India represents the sort of major emerging market it wants to do more business with as it looks to insulate itself against geopolitical shocks caused by the Trump administration in Washington.

Russia and India enjoyed a decades-long alliance forged during the Cold War, when the Soviet Union was New Delhi's largest trading partner, diplomatic ally and main arms supplier.

But the relationship became unmoored following the collapse of the USSR, as India underwent an economic transformation and increasingly sought to build trade ties with Western nations. That process has accelerated in recent years as New Delhi has orbited closer to Washington, and Russia has fostered relationships with India's chief regional rivals Pakistan and China.

Modi and Putin are expected to oversee a number of deals and discuss a framework agreement for Moscow to supply more reactors to a nuclear plant in southern India as the country seeks to reduce its reliance on highly polluting coal.

A revival of two-way trade, which slumped to below $8 billion in 2015 despite an ambitious bilateral target of $30 billion by 2030, will be a key priority during Modi's visit, who already met the leaders of Spain and Germany, and before travelling on to France next week.

Russia back on the agenda

While India will occupy pole position at the forum, other visiting international leaders include UN Secretary General Antonio Guterres and Austrian Chancellor Christian Kern.

Bosses from Chevron, Exxon and Boeing are among 144 US firms at the event, the best attendance in years after Washington previously warned business leaders against attending due to political tensions.

While Russia is talking up its recovery, the situation remains precarious and attention will also focus on talk of much-needed reforms to modernise its creaking economy.

uhe/jd (Reuters, dpa, AFP)