A royal commission should be established to examine the impact on hundreds of children being detained for long periods in immigration detention centres, a report prepared by the Australian Human Rights Commission inquiry has recommended.

The report, The Forgotten Children, has also called for all children to be released from mainland detention and from the detention centre on Nauru after examining hundreds of cases of assault against children, including more than 30 incidences of sexual assault.

It was tabled late on Wednesday night - the last possible day it could be tabled - after being handed to the Abbott government on November 11.

The inquiry staff interviewed 1129 children over a 15-month period from January 2013 to March 2014, spanning both the Labor and Coalition governments. It shows there were 233 recorded assaults involving children and 33 incidents of reported sexual assault.