Samaraweera, in New Delhi on a two-day visit to brief the Indian government on the faltering peace efforts, said the rebel Liberation Tigers of Tamil Eelam (LTTE) must bear full responsibility if the four-year peace process collapsed.
"The international community must bring pressure on the LTTE by using all powers within them to get them back to the table," Samaraweera told a press conference. "Something that hurts them the most is curtailing their fund raising activities," he added.
On Tuesday, the LTTE met Japanese special peace envoy Yasushi Akashi in rebel-held territory and appealed to him to persuade the Sri Lankan government to halt spiraling violence in the country.
The government has similarly called on the LTTE to halt violence that threatens a ceasefire that has been in place since 2002.
The two sides last held talks on salvaging the ceasefire in Switzerland in February.
The two parties agreed to meet again on April 19, but the Tigers declined citing continued violence by all