Curtin University political analyst Professor Joe Siracusa says America’s response to if Russian President Vladimir Putin used tactical nuclear weapons would “put us right at the doorstep of World War III”.

Professor Siracusa’s remarks come after the United States decided to allow the allies to supply F-16 fighter jets to Kyiv.

“I believe that President Putin is very seriously considering his options – one of them might be a tactical nuclear weapon,” he told Sky News Australia.

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