Prime Minister Narendra Modi and Russian President Vladimir Putin will primarily focus on pressing global and regional issues, including impact of the United States withdrawal from the Iran nuclear deal, during their informal summit in Russian city of Sochi on Monday.
Official sources said the two leaders will meet for around four to six hours for the 'agendaless' talks where deliberations on bilateral issues are likely to be very limited.
They said the issues on the table may include economic impact on India and Russia in the wake of the US withdrawal from the Iran nuclear deal, situation in Afghanistan, Syria, threat of terrorism and matters relating to upcoming SCO (Shanghai Cooperation Organisation) and BRICS (Brazil, Russia, India, China, South Africa) summits.
The sources said possible impact of the US sanctions against Russia under Countering America's Adversaries through Sanctions Act (CAATSA) on Indo-Russia defence cooperation may also figure during the talks between Modi and Putin.
India is not going to allow its defence engagement with Russia to be dictated by any other country, the sources said, adding New Delhi has been lobbying with the Trump administration on the issue.
The aim of the informal summit is to use the friendship and trust between the two countries to create convergence on key global and regional issues, the sources said.
There have been apprehensions that the US decision on Iran deal may adversely impact New Delhi's oil import from the Persian Gulf nation as well as on the Chabahar port project. Iran is the third largest supplier of crude oil to India after Saudi Arabia and Iraq.
Countries having financial dealings with Iran are expected to be hit by the comprehensive sanctions regime announced by the Trump administration after withdrawal from the nuclear deal.
The US had imposed sanctions on Russia earlier this year under CAATSA for its military intervention in Ukraine and alleged meddling in the 2016 US Presidential elections.
The two leaders may also deliberate on extending Indo-Russia civil nuclear cooperation in third countries, possible areas for cooperation for the International North–South Transport Corridor (INSTC) project, India's engagement with five-nation Eurasian Economic Union (EAEU) and the situation in the Korean peninsula.
The sources said the large part of the informal meeting between Modi and Putin will be one-to-one and there may be limited segment for restricted delegation level discussions.
They said President Putin will to also host a lunch for Modi.
The Russian President is also meeting German Chancellor Angela Merkel and French President Emmanuel Macron in the next few weeks.
It would be Modi's second informal summit in as many months as he held talks with Chinese President Xi Jingpin in China's Wuhan in a similar format last month.
Sources said there could be more such informal summits between Modi and other world leaders in the coming months as India eyes to play an important role in global power dynamics.
They said President Putin will be in India later this year for the annual summit during which key bilateral issues will be deliberated upon.
Last week, the ministry of external affairs said it will be an important occasion for the two leaders to exchange views on international matters in a 'broad and long-term perspective" with the objective of further strengthening 'special and privileged strategic partnership' between the two countries
The annual summit talks between the top leadership of the two countries have been taking place alternately in Moscow and New Delhi since 2000.
Modi is likely to reach Sochi on the morning of May 21.