Britain called on Tuesday for calm between Indian and Pakistani communities in London after lawmakers voiced concerns that tensions over a deadly militant attack in India's Kashmir region could spill into the diaspora.

India blames Pakistan for an attack on its tourists and threatens to disrupt Pakistani water supplies. Islamabad says that move would be an act of war.

Hindu-majority India has been fighting an armed insurgency in Kashmir for decades, though in recent years the situation had improved. The picturesque region is claimed in full by both India and Pakistan but ruled only in part by the neighbours.