World powers have condemned North Korea for test-firing a series of missiles, including one thought capable of reaching the US.
The Taepodong-2 may be able to reach Alaska
The seven missiles included a long-range Taepodong-2, which the US said failed shortly after take-off.
The US called the tests "provocative", and urged a resumption of multilateral talks. Japan went on to announce a range of sanctions against Pyongyang.
The UN Security Council has held an emergency meeting on the crisis.
The ambassadors of the US, Japan and the UK said there had been widespread concern with not a single member of the council defending North Korea's actions.
A draft resolution drawn up by Japan and the US is said to demand that Pyongyang immediately stop the development, testing and deployment of ballistic missiles.
It also calls on member states to prevent the transfer of resources, items and technology that could contribute to North Korea's missile programme.
Experts are beginning discussion on the document but there is no indication when it may be passed by the council.
Tokyo - one of North Korea's harshest critics, and in easy reach of a long-range missile - has already said it will ban the entry of North Korean officials, chartered flights and a ferry.
In its first response to the tests, China urged all sides to remain calm.
Japanese and South Korean military are on high alert, and share prices have fallen in both countries.
Pyongyang remained defiant. A foreign ministry official said such launches were a matter of national sovereignty, Japanese media reported.
The BBC's Charles Scanlon in Seoul says the North has been feeling under pressure and ignored in recent months, with the US refusing to negotiate on its demands over its nuclear plans.
US Secretary of State Condoleezza Rice said the strong reaction from the international community demonstrated that this was not a matter between the US and North Korea.
Ms Rice said the six-party talks provided the forum for discussing the missile crisis.
Without specifying what punitive measures the US could take, she said: "The international community does have at its disposal a number of tools to make it more difficult for North Korea to engage in this kind of brinksmanship and to engage in the continued pursuit of its nuclear weapons programmes and of its missile programmes."
Some observers believe it was not a coincidence that North Korea launched six of the missiles as the US celebrated its Independence Day holiday and launched the space shuttle from Florida.
NORTH KOREAN MISSILE MOVES
1998: Tests long-range Taepodong-1 over Japan
1999: Agrees to moratorium on long-range tests
2003: Six-nation talks begin on N Korea's nuclear programme
2005: Six-nation talks stall
July 2006: N Korea launches seven missiles, including long-range Taepodong-2, which fails
According to US officials, the six earlier launches took place over a four-hour period, beginning at 0332 Japan time (1832 GMT Tuesday).
Among them was the Taepodong missile - thought capable of reaching Alaska. US officials said it failed shortly after take-off, while the others fell into the Sea of Japan.
The seventh missile launch came hours later, at 1722 Japan time (0822 GMT) according to local media reports.
The US and North Korea's neighbours have been on heightened alert in recent weeks amid suspicions that Pyongyang was preparing to launch the Taepodong-2, which has a range of up to 6,000 km (3,730 miles).
It was Pyongyang's first test of a long-range missile since a self-imposed moratorium in 1999.
The last time North Korea tested a long-range missile was in 1998, when it launched a Taepodong-1 over northern Japan.