Indian prime minister Manmohan Singh warned Pakistani president Asif Ali Zardari today his country's territory must not be used for terrorism.
The two men were meeting for the first time since last November's attacks in Mumbai.
"I am happy to meet you, but my mandate is to tell you that the territory of Pakistan must not be used for terrorism," Mr Singh told Mr Zardari at a meeting on the sidelines of a Shanghai Cooperation Summit in Russia.
His tough words suggested there would be no dramatic breakthrough in relations between India and Pakistan. Washington is keen to see a thaw between the two countries to ease tensions across the region, including in Afghanistan.
India broke off talks with Pakistan after 10 gunmen launched multiple attacks on Mumbai last November, killing 166 people. It blamed the Pakistan-based Lashkar-e-Taiba militant group. Pakistan wants to resume a five-year-old peace process, but India has said it wants Islamabad to take further action against the Lashkar-e-Taiba first.
Ahead of his meeting with Mr Zardari, Mr Singh urged regional cooperation against terrorism and other security threats.
"The spectre of terrorism, extremist ideologies and illicit drug trafficking haunts our region. Terrorist crimes committed today are transnational in nature," he said in the text of the speech prepared for the summit.
"It is imperative that we genuinely cooperate with one another and on a global scale to resolutely defeat international terrorism."
India was incensed when a Pakistani court this month ordered the release from house arrest of Hafiz Mohammad Saeed, the founder of the Lashkar-e-Taiba.
Islamabad says it has detained some militants, but needs more evidence from New Delhi for further action.
The United States is keen to see the two countries improve relations so that Pakistan can concentrate on fighting Taliban militants on its western border with Afghanistan.
India and Pakistan are both observer states in the Shanghai Cooperation Organisation, which groups Russia, China and the former Soviet Central Asian republics.