Washington (CNN) Senators will be able to start reading the FBI investigation summaries into President Donald Trump's Supreme Court nominee Brett Kavanaugh on Thursday morning, Senate sources told CNN.

Senate Judiciary Chairman Chuck Grassley is expected to read the summaries first, followed by the top Democrat on the committee, Sen. Dianne Feinstein of California.

What will be included in the summaries and the exact timing remained to be determined Wednesday night. The White House expects to receive the results of an FBI background investigation into Trump's nominee "soon," officials told CNN. As of earlier Wednesday evening the documents, which several key senators have said they're waiting on before deciding how to vote, had not yet arrived. Sources say the Senate may physically receive the investigation Wednesday night but reading starts Thursday morning.

The future of Brett Kavanaugh's nomination to the high court appears on hold as key lawmakers await the FBI's findings, following a day of being asked to respond to Trump's mocking of the woman who accused Kavanaugh of sexual assault.

The FBI interviewed more people Wednesday as part of its investigation into the allegations of sexual assault and sexual misconduct leveled against Kavanaugh, a person familiar with the interviews told CNN.

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