One of Australia’s most senior spy masters has reportedly personally telephoned an undisclosed number of Liberal-National MPs to warn them of the dangers of publicly criticising Islam.

ASIO director-general Duncan Lewis made the phone calls in an effort to persuade the politicians to speak more ‘soothingly’ about the religion, The Australian reported exclusively on Thursday morning.

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The warning reportedly angered some of the MPs involved, who considered it an improper intervention in politics and a restriction of free speech.

Mr Lewis, a former army general and advisor to Julia Gillard and John Howard, reportedly made the phone calls at the behest of the Prime Minister’s office. The calls could be an unprecedented involvement in politics by an Australian spy master, according to The Australian.

During the phone calls, the ASIO boss reportedly told the MPs to adopt the more soothing style used by Prime Minister Malcolm Turnbull.

His agency is concerned that public criticism of Islam and its adherents could incite backlash against Muslims, increasing the risk of radicalisation. This is supported by Mr Lewis’ recent public comments, reported by News Corp and Fairfax.

ASIO has not publicly confirmed or denied The Australian‘s report.

—with AAP