LONDON (Reuters) -Britain's national broadcaster said on Thursday it would no longer broadcast or stream live any music gig deemed "high risk" after it was widely criticised for showing punk-rap duo Bob Vylan chanting against the Israeli military at Glastonbury.

The BBC had already said it should have cut the stream from Bob Vylan's performance at the music festival on Saturday which included on-stage chants of "death, death to the IDF", a reference to the Israel Defense Forces fighting a war in Gaza.

British police have since launched a criminal investigation for possible public order offences. Prime Minister Keir Starmer condemned the BBC for showing the performance, while media regulator Ofcom said the broadcaster had questions to answer.

The BBC has described the chants as antisemitic. Publishing an apology to viewers on Thursday, it said it was taking action, including the policy change over live broadcasts of certain music acts.

"We deeply regret that such offensive and deplorable behaviour appeared on the BBC and want to apologise to our viewers and listeners and in particular the Jewish community," the BBC said in its latest statement.

Before Glastonbury, the BBC had identified Bob Vylan plus six other acts as being high risk, it said.

Bob Vylan, known for mixing grime and punk rock, tackle a range of issues including racism, homophobia and the class divide in their songs and have previously voiced support for Palestinians.

Their lead vocalist, who goes by the stage name Bobby Vylan, appeared to refer to the weekend performance in a post on Instagram, writing: "I said what I said."

"Teaching our children to speak up for the change they want and need is the only way that we make this world a better place," he added.

The duo's performance at Glastonbury was monitored, the BBC said, and although more senior staff members were alerted, the editorial team decided not to cut the feed, which the broadcaster said was a mistake.

"We are taking actions to ensure proper accountability for those found to be responsible for those failings in the live broadcast," the statement added.

(Reporting by Sarah YoungEditing by Ros Russell)