WASHINGTON — North Korea has not completed the steps needed for testing a long-range missile, a leading senator said Tuesday after a private briefing from Defense Department officials.

"There are certain steps that would have to be taken if it were imminently to be launched. And those steps, as yet, have not taken place," said Sen. John Warner, R-Va., chairman of the Armed Services Committee.

Warner said North Korea would have to "remove certain infrastructure" before a missile could be launched, though he did not specify what he meant. Satellites would detect those steps, he said.

The remarks by Warner seemed to raise more doubts about whether a launch was imminent than other U.S. officials have so far expressed. Last week U.S. officials said the missile was apparently fully assembled and fueled, though they later said it was unclear how ready the North Koreans actually were.

Even so, President Bush has asked North Korea to declare "what they have on top of that vehicle and what are their intentions," and joined with other countries in warning them not to launch it.

Warner also said he supported administration officials who have said the confrontation should be handled by diplomacy, not an attempt to destroy the missile before it can be launched.

"I think that the administration has pretty well put to rest, and I concur with the administration," he said. "A pre-emptive strike at this point in time would not be a wise course of action.

Warner spoke to reporters after defense officials briefed his panel behind closed doors on the possibility of a launch.

The committee requested the briefing following intelligence reports that North Korea may be fueling a Taepodong-2 at a launch site on the country"s northeastern coast. The missile is believed to be capable of reaching parts of the United States.

North Korea has said it has produced nuclear weapons, though it is unclear whether they could place such weapons on the missile.