Tokyo, Japan (CNN) -- Paris Hilton left Japan late Wednesday afternoon after initially being refused entry because of a drug conviction, immigration officials said. The American socialite was heading back to the United States "after a lengthy delay at Japanese immigration," her spokesman said Wednesday. "Paris is very disappointed and fought hard to keep her business commitments and see her fans, but she is forced to postpone her commitments in Asia," the spokesman said. She arrived in Japan on Tuesday and had been allowed to spend the night, to see whether immigration officials would reconsider their initial refusal to allow her entry. Hilton left about 4 p.m. Wednesday, before they reached a final verdict, said an immigration official at Narita Airport.
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NEW: Hilton is "very disappointed" and fought to stay in Japan
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The socialite is headed back to the U.S.
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She pleaded guilty to a drug charge earlier in the week in Las Vegas
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Hilton was traveling on business, a spokesman said
"@placeholder understands and respects the rules and laws of the immigration authorities in Japan and fully wishes to cooperate with them," the spokesman said.