Australia's national intelligence agency said in a report this week that it does not have enough resources to collect intelligence on foreign agents and their efforts to interfere.

Australia, a staunch U.S. ally, has been on heightened alert against the threat of home-grown radicals after several "lone wolf" attacks in recent years.

But the Australian Security Intelligence Organization (ASIO) said that as it focuses on those threats, intelligence gathering on foreign interference is falling short.