The 35-year- job will cover both domestic and foreign policy.
， who is married to Ivanka Trump， interests.
Democrats immediately called for a review of the appointment， citing nepotism laws and potential conflicts.
and the Office of Government Ethics to step in.
Earlier， Mr Trump hailed his son-in- asset' and he was proud to give him a 'key leadership role' in the administration.
will be inaugurated as the 45th president on 20 January.
Members of Mr Trump’s team have argued that a law barri positions.
’s lawyer has said he would step down as boss of his family’ job， and extricate himself from some of his assets.
Jamie Gorelick of law firm WilmerHale said was committed to complying with federal ethics laws and had consulted with the Office of Government Ethics about what steps to take.
was often seen by his father-in-law’s side during the presidential campaign and was heavily involved in its digital strategy.