Al Gore presents green award to Charles

Former Vice-President Al Gore presented Britain's Prince Charles with an award for his work on behalf of the environment, as the Prince of Wales and his wife, Camilla, wrapped up their weekend trip to the United States.

Gore, who served under President Clinton in the 1990s, presented Charles with the Global Environmental Citizen Award, given by the Center for Health and the Global Environment at Harvard Medical School.

In a speech delivering the award Gore praised the prince's knowledge and passion, and said he and the prince have had conversations about the environment for 20 years.