US President-elect Donald Trump appoints his son-in-law Jared Kushner as a White House senior adviser Monday Jan 09,2017

US President-elect Donald Trump appointed his influential son-in-law Jared Kushner as a White House senior adviser Monday Jan 09,2017, putting the young real estate executive in position to exert broad sway over both domestic and foreign policy, particularly Middle East issues and trade negotiations.

Donald Trump has come to rely heavily on Kushner, who is married to the president-elect's daughter Ivanka. Since the election, the political novice has been one of the transition team's main liaisons to foreign governments, communicating with Israeli officials and meeting Sunday with Britain's foreign minister. He's also huddled with congressional leaders and helped interview Cabinet candidates.

Ivanka Trump, who also played a significant role advising her father during the presidential campaign, will not be taking a formal White House position. Transition officials said the mother of three young children wanted to focus on moving her family from New York to Washington, though a person with knowledge of the decision said her business, a clothing line and lifestyle brand, was complicating her move into government.

Kushner's own eligibility for the White House could be challenged, given a 1967 law meant to bar government officials from hiring relatives. Kushner lawyer Jamie Gorelick argued Monday that the law does not apply to the West Wing. She cited a later congressional measure to allow the president "unfettered" and "sweeping" authority in hiring staff.

In a statement, Trump said Kushner will be an "invaluable member of my team as I set and execute an ambitious agenda."

Kushner will resign as CEO of his family's real estate company and as publisher of the New York Observer. He will also divest "substantial assets," Gorelick said. The lawyer said Kushner would not be taking a salary. Ivanka Trump will also be leaving her executive roles at the Trump Organization - her father's real estate company - and her own fashion brands.

Kushner, who turns 36 on Tuesday Jan 10,2017, emerged as one of Trump's most powerful campaign advisers during his father-in-law's often unorthodox presidential bid - a calming presence in an otherwise chaotic campaign. Soft-spoken and press-shy, he was deeply involved in the campaign's digital efforts and was usually at Trump's side during the election's closing weeks.

He has continued to be a commanding presence during the transition, working alongside incoming White House chief of staff Reince Priebus and senior adviser Steve Bannon. He's played a key role in coordinating Trump's contacts with foreign leaders and has been talking with foreign government officials himself, according to a person with knowledge of the conversations.