Union Minister Harsh Vardhan, who participated in International Yoga Day celebrations in West Bengal, on Sunday described the mammoth event as the "largest ever expression of unity"."On World Yoga Day please participate in the largest ever expression of 'unity' thanks to our PM's initiative. World feels indebted to our PM," Vardhan, the Science & Technology, Earth Sciences Minister, tweeted."World Yoga Day generating tremendous response among Nehru Yuva Kendra volunteers, students and youth. Feel proud to be with them in Kharagpur," he said.The minister, who was seen dressed in a white tee with the Yoga Day logo, said he was privileged to have participated in the workout session in Bengal, which he said, is a land of many famous yogis."In land of Sri Aurobindo, Yogananda and many famous Yogis -- Bengal -- I find myself privileged to celebrate 'World Yoga Day' inspired by PM," the well-known ENT surgeon said."Patanjali founded Yogasutra, Baba Ramdev popularised Yoga in India. Now PM Narendra Modiji is globalizing Yoga. Feel proud to be Indian," he added.