A furious diplomatic row between India and Canada has pushed an otherwise fringe separatist campaign for an independent Sikh homeland in Punjab into the international spotlight.

The plot allegedly targeted Khalistan movement leader Gurpatwant Singh Pannun, who has vowed to continue his campaign. The FBI said it would not tolerate acts of violence or retaliation against people living on US soil.

There are roughly 770,000 Sikhs in Canada, about 2 per cent of the population - the largest Sikh community outside India Ottawa's accusations this week detailing a deadly Indian campaign against its Canada-based critics may have further derailed bilateral relations - but to Sikh activists,