UN Secretary-General Antonio Guterres has called for an agreement to achieve net zero emissions by 2050 and accelerated decarbonisation efforts at maritime transport talks in London. Shipping, which transports around 90 per cent of the world's merchandise and accounts for around 3 per cent of emissions, is facing calls from environmentalists and investors to take more concrete steps, including a carbon tax. "I invite the industry to leave London having agreed on a greenhouse gas strategy that commits to net zero emissions by 2050 at the latest," said UN Secretary-General Antonio Guterres.