Paltrow, 41, and the 37-year-old musician married in 2003. They have two children: 9-year-old daughter Apple and 7-year-old son Moses.
"We have been working hard for well over a year, some of it together, some of it separated, to see what might have been possible between us, and we have come to the conclusion that while we love each other very much we will remain separate," read the message titled "Conscious Uncoupling" on Goop.com.
It was signed by both Paltrow and Martin, and a spokeswoman for Martin confirmed the separation.
"We are parents first and foremost, to two incredibly wonderful children, and we ask for their and our space and privacy to be respected at this difficult time," the message also said. "We have always conducted our relationship privately, and we hope that as we consciously uncouple and co-parent, we will be able to continue in the same manner."
Martin, the Grammy-winning lead vocalist of Coldplay, and Paltrow, who won an Oscar for her performance in "Shakespeare in Love," were among Hollywood's highest profile couples. The duo frequently accompanied each other to public events, such as this year's Golden Globes ceremony and the Help Haiti Home gala earlier this year, but they rarely posed together on red carpets.
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