Eminem has called a truce with Mariah Carey. The stars have had a long-running feud since they were romantically linked several years ago. Eminem, who recently checked into a rehab clinic, has written a letter of apology to Mariah, asking her to put their differences aside and be friends. One source said: "Facing up to the past and writing to people who have been closest to you is one of the steps people take in rehab." Mariah recently branded Eminem a liar after he claimed to have had an affair with her. Just days after the troubled rapper checked into a rehab clinic for a sleeping pill addiction in August, the pop diva has vehemently denied he bedded her. She said: "I knew him, I hung out with him a few times, but nothing ***ual occurred. Maybe he thought he'd look bad or something." Mariah's angry comments come after she slammed Eminem for playing her personal answer-phone messages during his concerts. The ***y singer was left furious when she discovered the star has been playing a recording of her phone messages during his Anger Management concerts.