John Legend, the R&B singer and songwriter, abruptly canceled a North American tour on Thursday that had been scheduled to start later this month, including an Oct. 29 appearance at the new Barclays Center in Brooklyn. He said he was having trouble finishing the album he had originally planned to release to coincide with the shows this fall.

In a letter to his fans posted on his website last Thursday, Mr. Legend said that he had fallen behind in the studio and had not yet finished “Love in the Future,” his first new album since “Wake Up!,” a retro-soul project with the Roots. The original plan, he said, had been to finish the album and start performing the new songs on this fall’s tour, which he had announced would begin in Clearwater, FL, on Oct. 16.