One Nation leader Pauline Hanson has accused women of making up domestic violence claims in order to get custody of their children, as she defended a new parliamentary inquiry into the family law system.

Domestic violence campaigner Rosie Batty meanwhile has called on Labor and the Greens to block the inquiry - of which Senator Hanson is set to be deputy chair - saying it is "completely unacceptable" for "politicians with their own agendas" to lead parliamentary investigations.

One Nation's Pauline Hanson says mothers are making up domestic violence claims to stop fathers getting access to their children. Credit:Alex Ellinghausen

In an interview on ABC's Radio National on Wednesday, Senator Hanson said she was hearing "too many cases" where "parents are using domestic violence to stop the other parent from seeing their children". Asked if she was saying mothers were going into the Family Court and making up accusations of family violence, the One Nation leader replied, "I am".

Senator Hanson was pressed several times by host Hamish Macdonald to provide evidence for her claim.