NSW Premier Kristina Keneally has accused former One Nation politician Pauline Hanson of racism, and says Labor will not support her comeback.

In a surprise move Ms Hanson revealed she has nominated to stand as an independent for the NSW upper house at this month's state election.

Ms Keneally said the Labor Party would direct no preferences to her.

"I want to make unequivocally clear that the NSW Labor Party will have no preferences for Ms Hanson," Ms Keneally told Fairfax Radio Network today.

"We absolutely condemn the sorts of racist and discriminatory policies which come from Ms Hanson and parties like One Nation."