First daughter and White House Senior Advisor Ivanka Trump says she doesn't feel she should share her opinions publicly when they diverge from her father's.

ABC News asked her why she did not speak out against President Donald Trump's policy to separate thousands of migrant children from their parents, after CNN reported last year that she had opposed it behind closed doors.

Trump said it is not her job "to share my viewpoint when they diverge."

She has defended her father's policies multiple times in the past, and told ABC news that she only considers speaking out publicly when she is not listened to behind closed doors.

First daughter and White House Senior Advisor Ivanka Trump said she feels she should only speak publicly about the Trump administration's policies when she agrees with her father.

In an interview with ABC News published on Friday, Trump was asked why she didn't speak out against President Donald Trump's family-separation policy, which saw thousands of children being separated from their families at the US-Mexico border.

She had opposed the policy behind closed doors when it was still ongoing, CNN reported. President Trump later signed an executive order to end it last June.

When asked why she didn't speak out at the time, Ivanka Trump told ABC News that it is not her job "to share my viewpoint when they diverge."

Ivanka Trump watches as President Donald Trump answers questions after signing an executive order intended to end the practice of separating family members apprehended while illegally entering the US in June 2018. Win McNamee/Getty Images

She only openly spoke out against the policy after her father signed the bill to end the practise.

She tweeted immediately after the president signed the executive order, thanking her father and saying that ending the practice was "critical."

Two months later, she described the policy as a "low point" of her White House tenure.

ProPublica reported in December that family separations were still taking place even after Trump's bill to end them.

Read more: Thousands more children were separated from their parents at the border than were previously known, inspector general reveals in bombshell report

Ivanka Trump has publicly defended a number of her father's most unpopular policies in the past, including his attitude towards women or the use of tear gas against migrants at the US-Mexico border.

Ivanka Trump in the Oval Office while her father signs a bill in January 2019. Mark Wilson/Getty Images

But she has also broken with his stances in a few instances, including telling Axios in August 2018 that does "not feel that the media is the enemy of the people" and calling his comments on the Access Hollywood Tape "clearly inappropriate and offensive.

"I think that when you hear me start to speak publicly on an issue that's active, it's because my voice isn't being heard privately," she told ABC News.

She also hit back at people who she says have "unrealistic expectations" about how much influence she can have other her father's agenda, as liberal critics urge her to be more outspoken.