WASHINGTON — The Bush White House condemned North Korea for its defiant missile tests and accused Pyongyang of trying to "intimidate other states" but said the missiles posed no danger to the United States.

The test-firings of six missiles — including a long-range missile designed to reach U.S. soil — which came as America celebrated the Fourth of July, raised the stakes in a nuclear standoff and pressured the U.S. and its partners to penalize Pyongyang. North Korea fired a seventh missile early today, after the initial round of U.S. reaction.

For now, talking is the order of the day. Japan asked the U.N. Security Council to hold an emergency session today. Tokyo was expected to present a U.N. resolution protesting the missile tests, which sent U.S. officials scurrying to telephones for urgent, long-distance diplomacy.

The long-range missile, called the Taepondong-2, failed less than a minute after liftoff. It's unclear what North Korea learned from launching the shorter and medium-range ones, which fell into the Sea of Japan, but could be capable of striking its neighbors.

"Regardless of whether the series of launches occurred as North Korea planned, they nevertheless demonstrate North Korea's intent to intimidate other states by developing missiles of increasingly longer ranges," White House press secretary Tony Snow said in a statement released late Tuesday night. "We urge the North to refrain from further provocative acts, including further ballistic missile launches."

In Brussels, meanwhile, the NATO North American Council met today and issued a statement expressing "grave concern" over the missile firings. The council said that North Korea's deployment of the missiles poses "a serious threat to the region and the international community at large" and requires "a firm response" from the world.

In Washington, Democrats also expressed concern.

"This is an incredibly immature regime in the North. That's the part that frightens me about them," Sen. Joseph Biden, D-Del, ranking Democrat on the Senate Foreign Relations Committee, said today.

"I'm not concerned immediately about their nuclear capability or anything coming close to reaching the United States in this decade and maybe beyond," Biden told CBS News. "But I do think they're so irrational ... that they may play a game of brinksmanship."

Democratic Gov. Bill Richardson of New Mexico, U.N. ambassador during the Clinton administration, told ABC News that North Korea's leader, Kim Jong Il, was using the missile firings to flex his muscle.

"He's trying to say, hey, I'm around. I'm a player ... He's crazy like a fox. He's unpredictable. He's reckless. But you have to take him seriously," Richardson said.

Donald Gregg, ambassador to Seoul during the administration of Bush's father, George H.W. Bush, agreed that the North Koreans were "far from being able to miniaturize a warhead to put on this missile." He called the test-firings "a very stupid move on the part of the North Koreans," and told ABC News that "what Kim Jong Il has done now plays into the hardliners who don't want to do business with us anyway."

The White House said the United States would continue to take all necessary measures to protect itself and its allies, yet further diplomacy, not military action, appeared to be the preferred course of action.

Secretary of State Condoleezza Rice and Christopher Hill, assistant secretary of state, began talking Tuesday with their counterparts in Japan, China, Russia and South Korea. Hill was being dispatched to the region for new rounds of discussions.

National Security Adviser Stephen Hadley was meeting today with his South Korean counterpart, a meeting that now will be dominated by the tests, which could plunge global relations with the reclusive communist nation farther into a deep freeze.

"We do consider it provocative behavior," Hadley told reporters in a telephone briefing Tuesday.

President Bush, who was at the White House with family and friends gathered to celebrate the Fourth of July and his 60th birthday on Thursday, was notified of the test firings, and consulted with Rice and Defense Secretary Donald H. Rumsfeld.