SAN FRANCISCO — Legendary gospel singers are voicing their support for a greener planet Earth. Not since the recording of “We Are the World” 20 years ago has the music industry come together for such a global issue.

“United Nations, Together We Can,” written and produced by legendary, four-time Grammy winner Edwin Hawkins (of “O Happy Day” fame), is being recorded this week. The song will debut with a 1,000-voice choir on “Flower Power Day” on the steps of San Francisco’s City Hall, at the closing ceremony of the United Nations World Environment Day June 5.

The nondenominational song is being recorded in Berkeley, Calif., and features gospel artists The Williams Brothers, Richard Smallwood, Daryl Coley, Three Bridges, Virtue, Walter Hawkins, Lashun Pace, Byron Cage, Tramaine Hawkins, Donald Lawrence, Tone’, Karen Clark-Sheard, Kim Burrell, and others.

Proceeds from the sale of the song will be donated to “A Community of Unity,” a nonprofit led by Hawkins that raises funds for a variety of San Francisco Bay Area charities.

“For the sake of our children, it is our responsibility to heal the planet,” said Hawkins. “We should take responsibility to maintain the natural resources we were given. I contributed this song to help raise awareness for the need for change before it is too late.”

Celebrity gospel and pop artists who participate in the recording will be invited to sing with the choir, at which UN Secretary-General Kofi Annan is scheduled to give the closing remarks. The ceremony will cap a weeklong series of environmental programs, including an international sustainable floral symposium, an environmental education program for local youth, and decorating the city with organic flowers and floral sculptures.