A Republican staffer resigned Monday morning after a backlash prompted by a Facebook post she wrote attacking the appearance and behaviour of U.S. President Barack Obama's teenage daughters.

Elizabeth Lauten told NBC on Monday morning that her resignation was "in the works" and shortly after the Washington Post reported she had confirmed her resignation to the newspaper.

The Obama girls, Malia, 16, and Sasha, 13, generated some lighthearted buzz on Wednesday when they accompanied their father to the annual Thanksgiving turkey pardon ceremony at the White House. They looked less than thrilled to be there.

Elizabeth Lauten, shown in her Facebook profile photo, resigned following a backlash over her Facebook post about the Obama daughters. (Facebook) Some media coverage and social media users noted their side-eye directed at their father and Malia's cool response of "Nah" when her dad asked if she wanted to pet one of the birds. They were acting like typical teenagers, people said.

But Lauten, communications director for Representative Stephen Lee Fincher, was apparently so deeply offended by the teenagers that she wrote a harshly worded Facebook post addressed to them.

"Try showing a little class," she wrote to Malia and Sasha. "At least respect the part you play. Then again your mother and father don't respect their positions very much, or the nation for that matter, so I'm guessing you're coming up a little short in the good role model department."

Lauten not only scolded the Obama daughters for looking bored, but for the way they were dressed.

"Dress like you deserve respect, not a spot at the bar," she wrote. "And certainly don't make faces during televised, public events."

Sasha wore a cardigan-type sweater over a burgundy dress and Malia wore a plaid skirt and sweater.

Lauten's post went viral and as it circulated on social media it drew a lot of criticism and some accusations of cyber bullying. Many came to the defence of the girls, saying the children of the president should be off-limits to critics and that Lauten went way too far.

Lauten apologizes for 'hurtful' words

Someone started a petition on change.org calling for Lauten to be fired. It said given her job as a communications director, her comments about the young women were particularly "horrifying."

U.S. President Barack Obama's daughters Sasha, left, and Malia smile as they listen to their father at the turkey pardoning ceremony at the White House. (Gary Cameron/Reuters) It didn't take long after her original post for the backlash to prompt Lauten to take to Facebook once again and offer an apology.

"When I first posted on Facebook I reacted to an article and I quickly judged the two young ladies in a way that I would never have wanted to be judged myself as a teenager," Lauten wrote Friday. "After many hours of prayer, talking to my parents, and rereading my words online I can see more clearly just how hurtful my words were.

"Please know, those judgmental feelings truly have no place in my heart. Furthermore, I'd like to apologize to all of those who I have hurt and offended with my words, and I pledge to learn and grow (and I assure you I have) from this experience," Lauten wrote.

Lauten's Facebook profile says she started working as Fincher's communications director in February 2013. Her Twitter profile says she loves God, cats and all things pink, green and pearls. Lauten at one time worked for the Republican National Committee.

The committee's communications director, Sean Spicer, wrote on Twitter Monday that while Lauten's comments were "inappropriate and insensitive," the mainstream media's coverage of the Lauten story is "appalling." Spicer wrote that in 20 years of working in politics he's never seen the same level of coverage applied to inappropriate comments made by Democrats.

White House spokesman Josh Earnest was asked about the controversy at Monday's daily press briefing and said he was "surprised" by what Lauten wrote and that apologizing was the appropriate thing to do.

Earnest said that as someone who works in communications like Lauten did, the incident serves as a reminder to choose words carefully and to be mindful of how they might be received.

Asked whether Malia and Sasha should be off-limits, Earnest said the principle of leaving the children of the president alone is "common sense."