Cash won't cop unnecessary amendments

The federal government will negotiate in good faith on legislation to reinstate the building industry watchdog but won't cop unnecessary amendments by the Senate.

Prime Minister Malcolm Turnbull is bringing back parliament early on April 18, challenging the cross bench to support legislation or face a double-dissolution election on July 2.

Employment Minister Michaelia Cash, who is overseeing the bills, told ABC TV she would negotiate in good faith, but won't tolerate "amendments just for amendments sake".