WASHINGTON — The Trump administration's intelligence watchdog has declined a request from four top Senate Democrats to investigate how the White House has handled security clearances for Jared Kushner, Ivanka Trump and other employees, according to a letter obtained by NBC News.

Michael Atkinson, the inspector general of the intelligence community, meaning the chief internal watchdog for the nation's intelligence agencies, wrote to the senators that he would be happy to conduct such an investigation, but could only do it if President Donald Trump asks him.

"The authority over access to classified information ultimately rests with the President of the United States," Atkinson wrote to Sen. Mark Warner of Virginia, the ranking Democrat on the Intelligence Committee, and the three other senators. "It is well-established that the President of the United States has broad latitude concerning the process through which security clearances are granted, transferred, or revoked, as well as broad flexibility in determining whom to choose as his advisors and to what extent those advisors may gain access to information, including national security information."

"Given the concerns raised by your letter, the ICIG is available and willing to conduct a review, similar to that suggested in your letter, at the request of the President or his designees," he added.

Click here to read Atkinson's letter.

In response, the senators — Warner, Dianne Feinstein of California, ranking member on the Judiciary Committee; Bob Menendez of New Jersey, ranking member on the Foreign Relations Committee; and Jack Reed of Rhoda Island, ranking member on Armed Services — wrote a letter to Trump on Wednesday asking him to order an investigation.

"Over the last two years, public reporting has raised serious concerns about irregularities and questionable decisions related to eligibility determinations for (White House) personnel access to classified information," the letter said.

Click here to read the senators' letter to Trump.