Lawyers working for Kate Winslet have threatened to sue a fathers' rights group after they used her image in a Christmas campaign.

The Oscar winner's picture appears on a new poster from Fathers4Justice, an organisation which calls for custodial rights for dads, in light of the mother-of-three's comments to Vogue magazine insisting she disagrees with "50/50" parenting.

Her ex-husband Sam Mendes blasted the advert, which features the tagline 'Kate, every child deserves a father this Christmas', and bosses of the organisation have revealed they have also been contacted by Winslet's legal team.

A copy of a letter sent by Winslet's attorneys has been posted on Facebook.com and accuses the Fathers4Justice poster of "misleading and seriously defamatory" remarks.

In a statement, Campaign Director Nadine O'Connor hits back at the accusations, writing on the site, "Kate Winslet brought her children/parenting arrangements into the public domain with her comments, not Fathers4Justice.

"We believe the content of the advert is accurate, balanced and reflective of the comments she made. We do though welcome Mr Mendes' comments supporting fathers rights and find it regrettable that instead of resolving this dispute as we had agreed, Kate Winslet has sought redress through legal action."

The Titanic star has three children by three different dads - a daughter, Mia, with first husband Jim Threapleton, son Joe with Mendes, and another son, born earlier this month (Dec13), with her third husband Ned Rocknroll.