Far-right Australian senator Fraser Anning was slapped by an egg at the back of his head during a news conference in which he seemed to justify the mosque attacks that jolted New Zealand on Friday.

The senator was restrained by security officials as he hit back at the young man who had egged him.

In his statement, Anning said that the attack, which killed worshippers in a southern New Zealand city, was the result of Muslim immigration into the country.

Prime Minister Scott Morrison condemned Anning's comments as "appalling" and "ugly", saying that such a stance has "no place in Australia".