Bernardi backs change to race hate laws

Labor says Cory Bernardi is again promoting prejudice by backing a bill to weaken race hate laws.

The conservative Liberal senator has co-signed a bill with the Liberal Democrats' David Leyonhjelm, which is intended to be introduced to the Senate on Thursday by Family First senator Bob Day.

The bill's intention is to strike the words "offend" and "insult" from section 18C of the Racial Discrimination Act, Fairfax Media reports, reducing the legal avenues for people who feel they have been wronged based on their race.

The push comes the same week the government is debating changes to national security legislation.

Labor multiculturalism spokeswoman Michelle Rowland called on Prime Minister Tony Abbott - who is in New York for UN talks to deal with the threat of foreign fighters joining Islamic State - to pull Senator Bernardi into line.

She said now more than ever politicians had a duty to promote harmony, tolerance and respect.

"Bernardi is once again promoting prejudice in the community," Ms Rowland said.

"It shows that the desire to bring back the right to be a bigot is alive and well within the Liberal party."