Sarah Palin is taking aim at politically correct secularists who want Christ airbrushed from the Christmas festivities and "Merry Christmas" replaced with "Happy Holidays".

She is currently on tour around the US to promote her new book, Good Tidings and Great Joy: Protecting the Heart of Christmas.

In the book, she claims there is a "war against Christmas" in the US being led by liberals and secularists.

This war, she writes, is the "tip of the spear in a larger battle to secularise our culture".

"Today, in too many respects, it's politically incorrect to acknowledge that Jesus is the reason for the season and Christ is the main part of Christmas," she told Newsmax.

"Those politically correct police . . . tell us that we must boot Christ out of Christmas. We're saying no, enough is enough of being intimidated."

Palin was greeted by 700 people as she kicked off her book tour in Bethlehem Township, Pennsylvania, wearing a sweatshirt that said 'It's OK to wish me a Merry Christmas!'.

The book offers her musings on the spirit of Christmas and personal anecdotes from how she celebrates the season with her family.

It is described by publisher, Broadside Books, as "a call to action to readers to defend and openly celebrate the joys of their Christianity, and to say to one another,'Merry Christmas!'."