LOS ANGELES — One of America’s most unlikely and riveting couples — Arnold Schwarzenegger, the Austrian body builder and movie star who became a Republican governor, and Maria Shriver, the journalist and member of the Kennedy dynasty — have separated.

Mr. Schwarzenegger and Ms. Shriver said in a statement Monday night that they were “amicably separating.” The separation came five months after Mr. Schwarzenegger finished his second term as governor of California and as people here were closely watching how the couple were adjusting to their new life. It was first reported by The Los Angeles Times.

Mr. Schwarzenegger had previously announced that he was returning to the movie business, but Ms. Shriver had not given any indication of what she would do next. “This has been a time of great personal and professional transition for each of us,” they said in the statement. “After a great deal of thought, reflection, discussion, and prayer, we came to this decision together. At this time, we are living apart, while we work on the future of our relationship.”