ACT senator Zed Seselja said he wasn't aware of the association between the phrase "it's OK to be white" and white supremacists, after he voted in favour of a One Nation motion using the words.

The Assistant Minister for Treasury and Finance was one of 23 government senators to vote for the motion moved by Senator Pauline Hanson on Monday afternoon, which acknowledged "the deplorable rise of anti-white racism and attacks on Western civilisation and that it is OK to be white".

ACT Liberal Senator Zed Seselja. Credit:Alex Ellinghausen

On Tuesday the government sought to distance itself from the motion, with the government's leader in the Senate Mathias Cormann blaming an "administrative process failure" that led to the government mistakenly voting in favour of the motion.

The motion was again put to the Senate chamber on Tuesday afternoon and defeated on the voices, after Minister Seselja defended it earlier in the day.