Tokyo - Britain's Prince Charles on Tuesday called for concerted efforts to build a low-carbon society to combat global warming while on a visit to Japan.

"We must not abandon the drive towards a low-carbon economy," the prince of Wales said in a speech marking the 150th anniversary of bilateral relations between Japan and Britain.

He arrived in Tokyo late Monday with his wife, Camilla, for a five-day visit.

The prince called climate change "the biggest challenge our planet has ever seen."

He said that even as the world now faces a financial crisis, it should not divert attention and efforts from protecting the earth.

"While we hope and pray that the underlying strengths of the global economy will enable it to bounce back, the effects of climate change will be far from temporary and will, indeed, be irreversible," he said.

Charles said rising sea levels would threaten coastal cities unless developed nations reduce their greenhouse gas emissions 70 to 80 per cent by 2050.

He urged technological innovation to achieve the goal, including energy-efficient technologies and conservation efforts, such as forest management.

The royal couple plans to visit a restored forest in Japan's north-central province of Nagano.

The prince last visited Japan 18 years ago when he came with his former wife, Diana, to attend Emperor Akihito's ascension to the throne.