As a key United Nations conference on climate change in Madrid entered its final days, Japan faced a barrage of criticism over its continued support for coal following a speech Wednesday by Environment Minister Shinjiro Koizumi.

Koizumi, speaking at the conference known as COP25, acknowledged the domestic and international criticism toward Japan's coal use, but defended the government's policy by saying the country was not getting enough credit for its efforts to move to other, more environmentally friendly energy sources.

"Of course I am aware of global criticism, including on our coal-related policies," Koizumi said. "A growing number of people in Japan, including myself, believe further climate actions must be taken."