Sens. Chuck Grassley, R-Iowa, and Richard Blumenthal, D-Conn., want answers about White House staffers working on interim security clearances.

In a letter to White House Counsel Don McGahn and FBI Director Christopher Wray, the two lawmakers ask for "clarity" on the process by which White House staffers apply for and receive security clearances.

The request comes on the heels of reports that 30 to 40 White House officials and administration appointees work without full security clearances and still have access to classified information.

Grassley, who chairs the Senate Judiciary Committee, and Blumenthal also want to know how many people working on Capitol Hill have interim security clearances.

Sometimes, an individual can see their interim security clearance "extended," say Grassley and Blumenthal, who also ask how many times this can happen.

"Are individuals at the White House who work with an interim security clearance barred from handling any matters or information that would otherwise be permissible if the individual had a full security clearance?" the letter asks. "Are individuals with interim security clearances granted access to the President’s Daily Brief?"

The letter to McGahn and Wray comes following the controversy involving Rob Porter, the former White House staff secretary. Porter had access to classified information without a permanent security clearance, and left the White House following allegations of domestic violence — allegations that reportedly reached White House chief of staff John Kelly.