Prime Minister Narendra Modi on Monday accused Pakistan of spreading terror and using terrorism as an instrument of state policy. And as the G20 Summit ended, Modi met the leaders of Britain, Argentina and Turkey.
Addressing G20 leaders, the Indian leader urged them to "isolate and sanction supporters of terrorism".
At the two-day summit held in the eastern Chinese city of Hangzhou, India raised the issue of terrorism at various sessions.
Modi told Chinese President XI Jinping how the scourge of terrorism was affecting the region.
"There are some nations that use it as an instrument of state policy. One single nation in South Asia is spreading agents of terror in our region," he said, without naming Pakistan.
India's ties with Pakistan have soured after Islamabad declared Kashmiri terrorist Burhan Wani, shot dead by security forces, as a "martyr".
"For us a terrorist is a terrorist," Modi said. He was speaking during his intervention at the last session of the G20 Summit.
"India has a policy of zero tolerance to terrorism. Because anything less than that is not enough," he said.
On the sidelines of the Summit, Modi met new British Prime Theresa May here, Argentine President Mauricio Macri and Turkish President Recep Tayyip Erdogan.
Modi said India viewed the UK as an important partner despite its decision to quit the EU. This was Modi's first bilateral with May, who succeeded David Cameron after the Brexit vote in June.
The issue of terrorism figured in the Modi-May meeting. They discussed enhancing counter terrorism cooperation. He called for greater collaboration in the area of cyber security and intelligence sharing.
May said she was keen to support Modi's vision for India and take forward the broader strategic partnership. She underlined the great importance the UK attached to the Indian diaspora.
She sought Modi's suggestions on further strengthening their partnership, particularly in trade and investment ties.
May said she backed Modi's reform agenda and that the UK was keen to participate in Make in India, Smart Cities and the Skill India Programme among others. The two leaders discussed their defence partnership.
Modi also met Argentina's newly elected President Macri and invited him to visit India, External Affairs Ministry spokesperson Vikas Swarup said.
The Indian leader said he would personally take him to the birthplace of Mahatma Gandhi, for whom Macri has had high regards. Macri recalled his two previous visits to India, as a tourist and as a Mayor.
Modi thanked Macri for Argentina's strong support for India's membership in the Nuclear Suppliers Group (NSG).
"The two leaders agreed to expand cooperation in areas such as agriculture, mining and hydro carbons," Swarup said.
"The President invited Indian companies to participate in the exploration of gas reserves in Argentina. He also sought Indian collaboration in the area of food security."
Speaking with the Turkish President, Modi raised the issue of India's membership to the NSG. In June, Turkey had teamed up with a group of countries to oppose India's membership to the 48-member cartel.
In New Delhi, President Pranab Mukherjee said India was a victim of cross-border terrorism, not a homegrown one.
"We certainly face attack but from cross-border terrorism. Success of our governance and administration lies in ensuring that homegrown terrorism, which is the world's biggest menace today, is not yet there in India," he told a group of students on the occasion of Teachers' Day.