An Australian daily accessed 22,400 leaked pages of classified data on India's Scorpene-class submarine.
Prime Minister Narendra Modi on Monday raised with French President Francois Hollande the leak of confidential data on the Indian Scorpene Class submarines being built in Mumbai in collaboration with French defence company DCNS on the sidelines of the G20 Summit in Hangzhou.
On the second and final day of the summit in this east Chinese city, PM Modi held separate "pull-aside" meetings with Mr Hollande and Turkish President Recep Tayyip Erdogan with whom he discussed India's NSG membership.
Prior to those meetings, PM Modi met Britain's new Prime Minister Theresa May and held discussions on "building opportunities" in the aftermath of UK's decision to exit the European Union.
In his meeting with Mr Hollande, PM Modi raised the leak of sensitive data related to Scorpene Class submarines. "This issue has also figured (in the talks)," External Affairs Ministry Spokesperson Vikas Swarup told reporters.
Over 22,000 pages of secret data on the capabilities of six highly-advanced submarines being built for the Indian Navy in Mumbai in collaboration with French defence company DCNS were leaked. The data leak reportedly happened overseas.
In his meeting with Mr Erdogan, the Prime Minister discussed the issue of India's membership of the 48-member Nuclear Suppliers Group (NSG), Swarup said.
The discussion with Mr Erdogan on NSG was significant as Turkey was among the few countries -- along with China -- which had stalled India's bid to join the elite grouping at its plenary meeting in June in Seoul.
China had then raised objection saying India was not a signatory to the Nuclear Non-Proliferation Treaty (NPT).
Turkey too raised its concern over the presence of supporters of dissident Muslim cleric Fethullah Gulen in India. Turkey accuses Fethullah Gulen of masterminding the failed July coup attempt.
Mr Swarup said enhancing civil aviation cooperation with Turkey also figured during the discussions.
With Theresa May, the Prime Minister underlined that even after UK's exit from the EU, "Britain remains an important partner" for India.
"May also referred to the recent passage of GST (bill) which would further boost trade and investment ties with the UK. She supported PM's reform agenda and the UK is keen to participate in Make in India, Smartcity and Skill India initiatives," he said.
The two leaders discussed further enhancing of the defence partnership and PM Modi invited UK firms to India.
They also talked about the challenges of terrorism, calling it "the biggest threat and danger to the world with no boundaries," Mr Swarup said.
PM Modi also invited Theresa May to visit India in her new capacity. Theresa May accepted the invitation and said would like to make as early a visit to India as possible, he said.
"Modi also touched upon UK's visa policy. In particular he said that the new UK regulations could have negative impact on Indian working professionals wishing to visit UK for short term business visits," Mr Swarup said.