Al and his wife, Tipper, shown here at the Presidential inaguration.

(CNN) – Former Vice President Al Gore and his wife, Tipper, have sent an e-mail to family friends announcing a mutual decision to separate, a longtime family friend told CNN.

“We are announcing today that after a great deal of thought and discussion, we have decided to separate,” the message said. “This is very much a mutual and mutually supportive decision that we have made together following a process of long and careful consideration. We ask for respect for our privacy and that of our family, and we do not intend to comment further.”

Gore spokeswoman Kalee Kreider confirmed the authenticity of the e-mail but declined to comment further.

The couple, married for 40 years, has four grown children and three grandchildren.

(Read More From CNN HERE)

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