A push to change Australia's race hate laws is effectively dead on arrival, with key Senate crossbenchers indicating they will block any major reform.

The Liberal Party is bitterly divided over changes to section 18c of the Racial Discrimination Act, which makes it illegal to offend, insult, humiliate or intimidate a person on the basis of their race, colour, national or ethnic origin. A fierce and long-running debate is expected to come to a head at party room meeting in Canberra on Tuesday.

In an extraordinary case of timing, the Coalition will debate removing protections in Australia's race hate laws on what is also the International Day for the Elimination of Racial Discrimination.

Prime Minister Malcolm Turnbull's ministry and then cabinet met on Monday night to discuss removing "offend" and "insult" from the act and replacing it with the word "harass", as well as other measures.