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.

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,

The two countries expelled each other's top diplomats Monday over an ongoing dispute about the killing of a Sikh activist in Surrey, BC.