Speaking on the Nova TV news channel on Monday, the ex-PM stressed withdrawal was the only moral option.
Agt said the Netherlands should withdraw because it was participating without any UN mandate in an illegal occupation.
The politician also said the US and Israel "repeatedly and seriously" breached international law and called the US "a rogue state".
Describing Bush's support for Israel as ''irresponsible and unjust'', the politician said the Dutch government and parliament would have to decide whether the troops would remain in Iraq or not.
Occupation axis member
Officially one of the US-British allies, the Netherlands currently deploys about 1300 troops to maintain security in a sparsely populated desert province in the south of Iraq since the summer of 2003.
They have patrolled a relatively peaceful area of Iraq, but with rising violence elsewhere, the province of al-Muthanna is also turning for the worse.
On Sunday, Dutch troops shot and killed an Iraqi after his car failed to stop at a checkpoint. The Dutch base in al-Samawa was also attacked with mortar grenades for the first time last Thursday.