Sen. Charles E. Grassley, R-Iowa. (Justin Wan/Sioux City Journal via AP)

Senate Judiciary Committee Chairman Charles E. Grassley (R-Iowa) wrote the director of the FBI on Monday and told him that the terse disclosure he provided to Congress on Friday about the discovery of additional potential evidence in the case of Hillary Clinton's use of a private email server “did not go far enough” and was thus unfair to Clinton, Congress and the American people.

“The American people deserve better than that,” Grassley wrote in the letter to James B. Comey, released  Monday afternoon.

“In the absence of additional, authoritative information from the FBI in the wake of your vague disclosure, Congress and the American people are left to sift through anonymous leaks from Justice Department officials to the press of varying levels of detail, reliability, and consistency,” wrote Grassley, who has been among the Republicans leading the congressional investigations into the email scandal.

Grassley followed up by asking Comey a series of questions about the email discovery and whether there is any preliminary information available.

The letter opens by thanking Comey for letting the Congress know of new information in the Clinton email matter. But Grassley quickly revealed that he was upset with Comey's limited disclosure in the brief letter the director sent to congressional committee chairmen last week.

“Unfortunately, your letter failed to give Congress and the American people enough context to evaluate the significance or full meaning of this development,” he wrote. “Without additional context, your disclosure is not fair to Congress, the American people, or Secretary Clinton.”

Grassley noted that Comey was in a tough position.

“You clearly faced a difficult decision about whether, what, and how much to disclose about this new information,” Grassley wrote." Some critics of your decision to update your testimony to Congress are inexplicably calling on you with their next breath to release even more information. While I disagree with those who suggest you should have kept the FBI’s discovery secret until after the election, I agree that your disclosure did not go far enough.”

Grassley told Comey that “the factual context is important.” In addition, he wrote, “it is critical for the public to know whether the FBI has requested from the Justice Department vital investigative tools such as grand jury subpoenas and search warrants and whether it has been denied access to them.”