DUBAI: The head of Iran's judiciary signalled Wednesday there would be fast trials and executions ahead for those detained in nationwide protests despite a warning from US President Donald Trump.

Iran's judiciary chief Gholamhossein Mohseni-Ejei made the comment in a video shared by Iranian state television online.

Mohseni-Ejei said: “If we want to do a job, we should do it now. If we want to do something, we have to do it quickly.”

He added: “If it becomes late, two months, three months later, it doesn't have the same effect. If we want to do something, we have to do that fast.”

His comments stand as a direct challenge to Trump, who warned Iran about executions an interview with CBS aired Tuesday:

“We will take very strong action,” Trump warned. “If they do such a thing, we will take very strong action.”