A senior Liberal has questioned whether a childless Julia Gillard can understand the way ordinary Australians think about their children having sex before marriage.

George Brandis suggested Ms Gillard was not qualified to comment on federal Opposition Leader Tony Abbott's controversial views about pre-marital sex given she does not have children.

"I think that any parent I can imagine would agree with Tony Abbott," he told ABC radio.

The opposition leader has stirred up a hornet's nest with his views on sex before marriage, advising his daughters not to "give (their virginity) to someone lightly".

While he acknowledges many people lose their virginity before their wedding day, Mr Abbott told The Australian Women's Weekly that if one of his three daughters were to put the question to him, he would tell them it was "the greatest gift that you can give someone".