Among the risks, say current and former intelligence officials and independent experts, are that top advisers could feed the incoming president a distorted view of global threats based on what they believe will please him and that foreign allies may be reluctant to share vital information.

Tulsi Gabbard - a former Democratic congresswoman who joined the Republican Party to back Donald Trump - is the president-elect's pick for director of national intelligence. The wide-ranging role would mean she oversees US intelligence agencies like the CIA, FBI and the National Security Agency (NSA), which focuses on intelligence gathering.

President-elect Donald Trump has appointed former Democratic Congresswoman Tulsi Gabbard as the new director of national intelligence. Gabbard, who was the first Hindu and first Samoan to serve in the U.