Cash comments 'ghastly', says Labor

Deputy Opposition Leader Tanya Plibersek has demanded a proper apology from cabinet minister Michaelia Cash for "ghastly, sexist" statements made about women working for Labor leader Bill Shorten.

Senator Cash withdrew comments she made in a Senate estimates hearing on Wednesday morning threatening to name women she said were the subject of rumours circulating around parliament.

Ms Plibersek said the comments were made with a 1950s mentality and the women subject to the comments deserved a proper apology rather than the "weasel word" withdrawal given by Senator Cash.