LONDON, June 8, 2010 (AFP) — US singer Chris Brown has postponed a series of concerts in Britain after being refused a visa over his sentence for assaulting ex-girlfriend Rihanna, his tour organisers and officials said Tuesday.

The 21-year-old was due to play four gigs here starting in Glasgow on Wednesday, but they have been put off after his visa application was turned down by the UK Borders Agency.

“Due to unforeseen circumstances the Chris Brown UK tour starting tomorrow… has unfortunately been postponed,” said tour promoter SJM Concerts in a statement on its website.

As well as the Glasgow concert, Brown was due to play in Birmingham, Manchester and London. SJM said fans should keep their tickets “as there will be more news in the forthcoming days of possible rearranged dates.”

The Home Office declined to comment officially, but sources confirmed that Brown had been refused a visa.

“We reserve the right to refuse entry to the UK to anyone guilty of a serious criminal offence. Public safety is one of our primary concerns,” said Barbara Woodward of UK Border Agency.

“Each application to enter the UK is considered on its individual merit,” she added.

Brown was sentenced to five years’ probation, a year-long domestic violence programme and 180 days of community labour after pleading guilty to assaulting Barbadian singer Rihanna on the eve of the Grammy Awards in February last year.

The incident shocked the music world and left Rihanna nursing cuts and bruises to the face, forcing her to cancel a performance at the awards show.

Affidavits in the case alleged Brown slammed Rihanna’s head against the window of a car the in which the couple was traveling, before punching and biting her.