Controversial Dutch politician Geert Wilders has released a provocative new video in which he calls on supporters to defend freedom of speech, by continuing to draw pictures of Mohammed, the founder of Islam - even in the face of deadly terrorist attacks by Muslim extremists.

Wilders was present at a Dallas, Texas "Draw Mohammed" competition in April, shortly before two Islamist terrorists attacked it with automatic assault weapons.

The two attackers - who swore allegiance to ISIS before opening fire - were themselves shot dead by a policeman guarding the event.

In the days and weeks following the attack, controversy swirled over the media's response to the incident, which saw organizers heavily criticized and even blamed for the attack on them. In response, many free speech advocates accused media outlets of "betraying" the cause of free speech.

That message was implicit in Wilder's video, which is reportedly due to be aired on Dutch TV.

In it, he criticizes the Dutch parliament for refusing to allow him to display drawings of Mohammed in the parliament building.

"Islam and the terrorists don't want us to show these cartoons. But terror and violence may never defeat free speech. That is exactly the reason why we should do what the terrorists want to prevent us from doing," he states, introducing a display of all the competition's cartoons - ending with the winning entry from artist and former Muslim Bosch Fawstin.