New Delhi, March 25 : The Ministry of Home Affairs issued an order prescribing a nationwide lockdown, soon after Prime Minister Narendra Modi announced for same in a televised address to the nation. The Centre cited 'proactive measures' such as ban on international travel, issue of advisories, setting up quarantine facilities, contact tracing of person infected with the virus, temporary suspension of metro, train service and domestic flights to fight against the coronavirus pandemic. The MHA said the situation is being continuously monitored at the level of PM Modi, who has already had video conferencing with the Chief Ministers. Experts have advised to stringently implant social distancing, given the experience of few other nations where the casualty rate has been way too high. However, the MHA adds that a lack of coordination between the Centre and the state won't help. Here, it says, NDMA, which is chaired by the Prime Minister himself, has issued an order to states and Union Territories to take effective measures to contain any further sed of the COVID-19. The order which will remain in force for the coming 21 days, has been followed by the MHA issuing an order directing states and UTs to take up effective measures. All concerned state governments and UTs have been asked to ensure "strict implementation" of the order, which the MHA says all be monitored by itself. Earlier tonight, Prime Minister Narendra Modi announced a three-week countrywide lockdown that will bring everything except essential services to a halt in India. Making a case for his decision, PM Modi said, "India is at the stage where our actions today, will decide to what extent we can bring down the impact of this disaster. This is the time to strengthen our resolve again and again." India's coronavirus infected patient count has surpassed 500. /IANS