Hongkongers are the biggest meat-eaters in the world, according to a group that is trying to change all that for the good of the planet by offering schoolchildren a vegetarian lunch once a week. Green Monday says the suppliers of lunch boxes to 350,000 children - 90 per cent of those who eat at school - have agreed to offer a meat-less option on Mondays from next month. The 17 suppliers have joined more than 300 restaurants, including Caffe Habitu, Pizza Express, Café de Coral, and the University of Hong Kong canteen that are backing the project. A United Nations study showed that the meat industry is responsible for nearly one fifth of the world's greenhouse gas emissions. This is more than the combined emissions of every car, train and plane. "Giving up meat just one day a week is an easy and effective way for you to make a difference," a spokeswoman for the group said. "It doesn't require a big lifestyle change or a huge time commitment. If everyone in Hong Kong gives up meat one day a week, it would be like taking 86,000 cars off the road." The group says Hong Kong comes top in a 2011 United States Department of Agriculture report on international meat consumption, the latest figures available. It adds the figures show each Hongkonger consumes 149.6kg of meat per year - exceeding Americans by 38 per cent. "Something needs to be done," the spokeswoman said as the group launched its Go Green Monday campaign yesterday. Monday was chosen as it offers a welcome change after a weekend of heavy eating, she said. One school meal supplier involved in the campaign said vegetarian meals had been unpopular until the campaign started raising awareness. Now meat-free meals account for 40 per cent of its orders on Mondays. The campaign spokeswoman said: "It is a good sign to show that parents and students are supportive towards the goal."