India's Space Research Organisation (ISRO) and French National Space Agency (CNES) would work together on the design and development of joint products and techniques to monitor and protect their assets in land and sea, said a document - Joint Vision for Space Cooperation - issued after talks between Prime Minister Modi and French President Emmanuel Macron.
On maritime security, the French President said both the countries will have "unprecedented" level of cooperation to ensure peace and stability in the Indian Ocean and Pacific.
The visiting leader asserted that the sea lanes can not be places for hegemonic power play, in a clear reference to China.
"European powers such as France and Germany are increasingly anxious about China's behavior". And its move into the vast Indian Ocean - stretching from the Suez Canal to the Malacca Strait - has heightened that concern. Modi had last visited France in June a year ago. The Indian Air Force has also been favouring procurement of more Rafale from France.
"The first [objective of my visit] is to seal for the decade to come a strong pact around collective security in the region between our two democracies", Macron emphasized. "The agreement is symbolic of the strategic depth and maturity reached in India-France defence ties", the joint statement said.More news: Miami nightclub closed after venue allows horse on the dancefloor
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The French president's visit comes just a week after the much-talked-about trip of Canadian prime minister Justin Trudeau to India. Macron will also visit Agra, and have a town hall interaction with students in New Delhi.
Earlier in the day, Mr Macron spoke about his personal rapport with Mr Modi which was established after their meeting in Paris past year. We can say this is going to be a new start of a good friendship. "I look forward to our talks tomorrow", Modi tweeted after receiving Macron at the airport.
"You welcomed me in Paris a year ago with an open heart and a lot of warmth. And I aim to have more and more Indian citizens coming to France studying, becoming a partner, creating start-ups and I want my country to be your best partner in Europe".
Under the terms of the agreement, Indian warships will have access to French naval bases in the Indian Ocean.
On Monday, he heads to the Hindu holy city of Varanasi on the banks of the river Ganges, which the Indian premier has promised to modernise and clean up.