Prime Minister Narendra Modi on Friday flagged off the world's longest river cruise -- MV Ganga Vilas, which will cover 3,200 kilometres across 27 river systems in five states in India and Bangladesh in 51 days.

MV Ganga Vilas is the first-ever cruise vessel to be made in India and it began its journey from Varanasi in Uttar Pradesh and will reach Dibrugarh in Assam via Bangladesh.