WASHINGTON (REUTERS) - US President-elect Donald Trump's son-in-law, Jared Kushner, will become a senior White House adviser working on trade and the Middle East, transition officials said on Monday (Jan 9), in a rare case of a close presidential family member taking a major job.

Mr Kushner, 35, who is married to Mr Trump's daughter Ivanka, is taking the post after receiving legal counsel that doing so would not violate US anti-nepotism law, transition officials said. The position, unlike Cabinet posts, does not require US Senate confirmation, and Mr Kushner will not be paid.

Mr Trump, in a statement on Monday announcing the choice, said Mr Kushner was a "tremendous asset and trusted advisor throughout the campaign and transition."

Mr Kushner, who like Mr Trump is a New York real estate developer, emerged as an important voice early in his father-in-law's presidential campaign and was involved in almost every aspect of it from personnel decisions to strategy and fundraising.

Ms Ivanka Trump, who like her husband has been a close adviser to the president-elect, will not take on a role in her father's White House but will focus instead on settling her family in Washington.

Mr Kushner and his wife will undertake significant divestment of their wide-ranging financial portfolios as they prepare for their move to Washington from New York and face inevitable questions about a potential conflict of interest.

Senior transition officials and a lawyer for Mr Kushner laid out the arrangement in a conference call with a small group of reporters.

Mr Kushner is to work closely with incoming White House Chief of Staff Reince Priebus and senior strategist Steve Bannon in advising the new president, and the officials said he would focus at least at first on trade policy and the Middle East.

Mr Trump, who takes office on Jan 20, has vowed to rewrite international trade deals to make them more favourable to the United States. He has also pledged to move the US Embassy in Israel from Tel Aviv, where it has been for 68 years, to Jerusalem, all but enshrining the city as Israel's capital despite international objections.

'WE HAVE THE BETTER ARGUMENT'

Ms Jamie Gorelick, a New York lawyer who served as deputy attorney general for Democratic President Bill Clinton and helped advise Mr Kushner, said his new post would not violate a 1967 anti-nepotism statute.

She said Congress in 1978 authorised the president to hire personnel for the White House office "without regard" to federal personnel laws like the anti-nepotism statute and that court rulings had determined the White House was not an "agency" under the anti-nepotism law.

"I'm not saying that there isn't an argument on the other side, and I respect the people who have made the argument on the other side. I just think we have the better argument," Ms Gorelick said.

Mr Richard Briffault, a government ethics expert at Columbia Law School, disagreed. "Given the fact that the president is specifically mentioned, you would think that someone that is working for the president would be covered" by the anti-nepotism law, he said.

In the early 1960s, Mr John F. Kennedy aroused controversy after his election as president by naming his brother Robert as attorney general.

DIVESTMENTS

In order to comply with federal ethics laws and after consulting the Office of Government Ethics, Mr Kushner will take a number of steps to divest substantial assets, Ms Gorelick said.

Mr Kushner will resign from his positions as chief executive of the Kushner Companies and as publisher of the New York Observer newspaper and divest from any interests in the New York Observer, Thrive Capital, the 666 Fifth Avenue office building in midtown Manhattan and any foreign investments.

In addition, Mr Kushner will recuse himself from participating in matters that could have a direct effect on his remaining financial interests.

Those interests include real estate in the New York area, Ms Ivanka Trump's interest in the new Trump hotel in Washington and the Ivanka Trump Brand fashion business, the officials said. Mr Kushner will file a public financial disclosure form.

Mr Norman Eisen, a former ethics chief under President Barack Obama, said in an email that Mr Kushner's ethics and disclosure moves appeared to be a "positive step".

"I hope his father-in-law takes a page from his book and does the same, as presidents have for the past four decades, by divesting into a blind trust or the equivalent," Mr Eisen said.

The president-elect has said he would transfer control of his business to his children, but he has given no details. A planned news conference in December on the topic was cancelled. Mr Trump is expected to take questions from reporters this week.

Ms Ivanka Trump will not participate in the management or operations of the Trump Organization, which she has helped run along with her two adult brothers. She also will not participate in running the Ivanka Trump brand or fashion business.

She will divest significant assets including all common stock and resign from all officer and director positions she holds in the Trump Organisation. ​