New Delhi: Congratulating Indian sportsmen and athletes, especially the "daughters of India" who performed well at the Rio Olympics, Prime Minister Narendra Modi on Sunday said there was clearly a need to do more to improve the country's medals tally Addressing the nation over radio in his 23rd Mann Ki Baat talk, he touched upon Kashmir, cleanliness, Ganga rejuvenation and environment conservation, among other issues. Modi also paid tributes to hockey legend Dhyan Chand on the eve of his 111th birth anniversary, and to Mother Teresa, who is to be canonised on September 4. Congratulating the athletes who performed well at the Rio Olympics, Modi stressed that sports should not be seen as a waste of time and that state governments must support and promote at least two sports of their choice. "Although our medals tally is just two, but many Indian sportsmen have performed quite well ... but we have to do more. If we keep doing what we have been, then we would face disappointment again. "I have announced a committee to look deeply into the matter. It would study the best practices (in sports) across the world and would prepare a roadmap on how to perform better at the 2020, 2024 and 2028 Olympics," Modi said. Touching upon the Kashmir situation, he said "unity" and "compassion" have been the key words while dealing with the unrest in the Valley, while shaming the troublemakers who were using children as shields. "In my interaction with different political groups, one thing emerged. It was unity and compassion to be the core mantra of our policy in Kashmir. "Those trying to incite trouble from behind children will have to answer for their deeds to these innocent children some day," he said. Raising concern over environmental degradation, Modi urged people to avoid using idols made of Plaster of Paris (POP) during the Ganesh Chaturthi and Durga Puja festivals. "Festival is the time of self-evaluation and they need to change with time. Environment is damaged due to immersion of POP idols. Let's go back to old traditions and adopt idols made of pond clay," he said. Paying tributes to Mother Teresa, Modi said that every Indian is feeling proud as she has officially been recognised as a saint of the Roman Catholic Church. "Mother Teresa devoted her whole life serving the poor and destitute people in India. When such a person is conferred with sainthood, it is natural for Indians to feel proud," he said, noting that despite not being an Indian, she had dedicated her whole life to serving Indians. The Prime Minister also praised a village pradhan from Karnataka for building a toilet in the house of a girl who staged a protest demanding a toilet. He appreciated Mohammad Shafi from Koppal district for building the toilet in the house of 16-year-old Mallamma, who demanded one but her poor parents could not arrange it. When Shafi heard about the matter, he arranged Rs 18,000 for the construction of a toilet in her house, Modi said. Modi also praised the 1.25 lakh students of 1,700 schools in Chhattisgarh's Kabirdham district for writing to their parents requesting a toilet in their house instead of spending money on birthdays. Emphasising that India has always striven for cordial relations with its neighbours, Modi mentioned the role of Akashvani Maitree channel in forging people-to-people contact between India and Bangladesh. He further stressed that people of India will certainly build a bright future for themselves if they remain united and promote unity and integrity.