Rapper Yasiin Bey, who most know as Mos Def (his former name), has canceled his upcoming U.S. tour because he is unable to gain entry into the country, he says.

According to a statement on the Boston Together Music Festival site, the 40-year-old is facing “immigration/legal issues” that are keeping him from being allowed back in the States, reports The Guardian.

The statement reads:

We regret to inform you that due to immigration/legal issues Yasiin Bey is unable to enter back into the United States and his upcoming U.S. tour has been canceled, including May 15, Together Boston’s show at The Wilbur Theatre. Individual ticket refunds for this show are available at point of sale.

It remains unknown what specific issues have led to Bey’s inability to return to the U.S. But over the past few years, the rapper has spoken out against and criticized several U.S. policies. He recently relocated to South Africa, telling Rolling Stone that he really connected with the energy of the country.

"I lived in Brooklyn 33 years of my life. I thought I'd be buried in that place. Around seven years ago, I was like, you know, 'I gotta go, I gotta leave.' It's very hard to leave. And I lived in a lot of places. Central America. North America. Europe for a while,” he told the magazine.

"And I came to Cape Town in 2009, and it just hit me. I was like, 'Yeah.’ I know when a good vibe gets to you. And, you know, I thought about this place every day from when I left. I was like, 'I'm comin’ back.'"

He added, "For a guy like me, who had five or six generations not just in America but in one town in America, to leave America, things gotta be not so good with America."