A federal judge has ruled that two Washington-based reporters must testify to a grand jury in the investigation into whether a member of the Bush administration illegally leaked to the media the name of a CIA employee's name.

On Monday, U.S. District Judge Thomas Hogan found that Tim Russert (search) of NBC's "Meet the Press" and Matthew Cooper (search) of Time magazine cannot use the Constitution's First Amendment (search) right in refusing to disclose conversations they may have had about Valerie Plame, the CIA employee married to Ambassador Joe Wilson.

In a ruling posted on the court's Web site dated Monday though issued on July 20, Hogan found Cooper and Time Inc. in contempt of court. The judge ordered Cooper confined until he is willing to comply with the grand jury subpoena to testify in the "CIA leak" probe case, but not for more than 18 months.

• Click here to read the order for contempt of court (pdf).

• Click here to read the memorandum opinion (pdf).

However, the judge stayed the ruling because of an appeal to the U.S. Court of Appeals (search) for the District of Columbia. Cooper was also ordered to pay a fine of $1,000 per day. The fine was also stayed.

"To be clear, this court holds that Cooper and Russert have no privilege, qualified or otherwise, excusing them from testifying before the grand jury in this matter," Hogan ruled in the 11-page opinion.

"There have been no allegations whatsoever that this grand jury is acting in bad faith or with the purpose of harassing these two journalists," the judge wrote.

Time Managing Editor Jim Kelly said he and Cooper are disappointed by the decision.

"We don't think a journalist should be required to give up a confidential source. We're going to appeal it as far as it goes," he said. 

Late Monday, NBC News issued a statement saying that Russert already had been interviewed under oath by prosecutors on Saturday under an agreement to avoid a protracted court fight. The interview concerned a July 2003 phone conversation he had with Vice President Cheney's chief of staff, Lewis "Scooter" Libby.

In the statement, NBC said Russert told Special Prosecutor Peter Fitzgerald that he did not know Plame's name or her identity as a CIA officer, and that he did not provide that information to Libby. The statement said that Libby had told the FBI about his conversation with Russert and requested that it be disclosed.

Neal Shapiro, president of NBC News, said the network agreed that forcing reporters to testify about their sources is "contrary to the First Amendment's guarantee of a free press." Shapiro said Russert answered "only limited questions" about the conversation with Libby "without revealing any information he learned in confidence."

Wilson last year publicly criticized President Bush for claims about Iraq he made in his 2003 State of the Union address (search). Shortly afterward, Plame's name was revealed in a July article by newspaper columnist Robert Novak.

Wilson went to Niger (search) in February 2002 to investigate claims that Iraq (search) tried to buy yellowcake uranium from the African nation. He accused the administration of leaking Plame's name after he publicly stated that Bush trumped up intelligence claims by British agents suggesting the charges were true. 

Bush cited British intelligence sources in his 2003 address, and those sources have since said they stand by the information. Shortly after the leak, however, the White House said the president should not have used the 16 words in his State of the Union speech.

Revealing the name of a covert agent is a federal crime. Bush, Cheney, Secretary of State Colin Powell and a host of other White House officials have been questioned about the source of the leak.

Fox News' Anna Stolley and The Associated Press contributed to this report.