Media playback is unsupported on your device Media caption Who is Heather Nauert?

US President Donald Trump's pick to be America's new UN ambassador, Heather Nauert, has withdrawn her nomination for the post.

Ms Nauert, a former Fox News presenter, said in a statement on Saturday that the decision was made "in the best interest of my family".

"The past two months have been gruelling," the statement, issued by the state department, said.

Mr Trump had announced Ms Nauert as his choice for the UN role last December.

"She's very talented, very smart, very quick, and I think she's going to be respected by all," the president said at the time.

Ms Nauert, who is currently serving as state department spokeswoman, would have replaced Nikki Haley, who announced in October that she would leave the post of UN ambassador by the end of the year.

Some had questioned whether Ms Nauert, who has been in government for less than two years and has never specialised in international relations, had sufficient experience to deal with the type of complex foreign policy issues tackled by UN ambassadors.

The role has often gone to skilled negotiators and leading names in US foreign policy - past ambassadors have been scholars, diplomats or prominent politicians.

Meanwhile, unnamed sources told US media that Ms Nauert took the decision to withdraw after the White House was made aware of an issue following a background check.

Bloomberg reported that she and her husband had employed an immigrant nanny who was in the US legally but did not have the correct work visa.

US Secretary of State Mike Pompeo said Ms Nauert had "performed her duties as a senior member of my team with unequalled excellence" and that she will "continue to be a great representative of this nation".

Who is Heather Nauert?

In addition to her state department role, the 49-year-old was also appointed acting undersecretary for public diplomacy and public affairs in March last year.

She worked for Fox News from 1998 to 2005 and, after two years away during which she worked for ABC, she returned to Fox in 2007, later becoming a presenter for Fox & Friends.

Fox News has been a consistent supporter of the president and he often cites its programmes.

Ms Nauert made headlines in June when, speaking in her state department role, she cited the World War Two Normandy landings in relation to America's "strong history" with Germany.