Canadian PM Justin Trudeau said he senses a change in India's tone with Ottawa after the United States warned New Delhi about its involvement in a thwarted plot to kill a Sikh separatist leader on US soil, the CBC reported on Wednesday. "I think there is a beginning of an understanding that they can't bluster their way through this and there is an openness to collaborating in a way that perhaps they were less open before," Trudeau said in the interview.