Brexit risks strengthening dissident republican groups and boosting organised crime, according to the first survey of links between terrorism and crime in the UK and Ireland.

Dozens of defectors have deserted Islamic State, shattering the group’s self-proclaimed image of a “jihadist utopia”, according to a new report.

Australia plans to pass a law within weeks to give the government power to strip citizenship from dual nationals who are suspected terrorists, even if they are not convicted of a crime, the prime minister said.