High level of air pollution over the southern Chinese city

China, the world's biggest greenhouse gas polluter, pledged Tuesday to peak emissions "by around 2030", Prime Minister Li Keqiang's office said in a statement.

Li made the undertaking to French President Francois Hollande, it said, during a meeting in Paris, which will host a year-end UN conference where leaders are meant to ink a new, global pact to curtail climate change through emissions curbs.