Lily Allen
PA Photos/Landov
The 22-year-old "Smile" singer had her American visa unexpectedly revoked Aug. 5 in Los Angeles, after she was searched and detained for five hours.
"The [visa] reinstatement process has proven lengthier than anticipated, thus preventing her tour from launching September 6th in San Diego, Calif.," Allen's rep said in a statement.
"I am so disappointed that I won't be able to come to the States at this time," Allen said in her own statement. "I was really looking forward to playing these shows and being part of the [MTV] Video Music Awards."
She added, "I want my fans to know that I'll be back as soon as I possibly can!"
Allen's unscheduled meeting with U.S. officials was triggered by Immigration and Naturalization Services concerns following her arrest in London in March, when she allegedly clashed with a photographer.
Earlier this month, Allen canceled four European shows because of illness.
The singer, who's home in London "eating my mum's chicken soup," is expected to appear at England's V Festival this weekend.
