Al Gore and wife Tipper to separate

Former U.S. vice-president and environmentalist Al Gore and his wife Tipper are separating after 40 years of marriage, a spokeswoman for Al Gore confirmed Tuesday.

"I can confirm . . . a separation (not divorce)," said Kalee Kreider in an email to Canwest News Service. "We are not commenting further."

An email sent to friends of the couple, and obtained first by the U.S. website politico.com on Tuesday, said the separation was "a mutual and mutually supportive decision that we have made together following a process of long and careful considering."

Gore, who lost the 2000 presidential election to Republican George W. Bush, has won notoriety for his commitment to educating the world about the dangers of climate change.

He won a Nobel Peace Prize in 2007 for his documentary "An Inconvenient Truth."

Mary Elizabeth "Tipper" Gore works as a photographer. She has chronicled her life as the vice-president’s spouse, as well as her husband’s 2000 presidential campaign.

The couple met at his senior prom in 1965 and married five years later.