The United States condemned North Korea's "highly provocative" launch of a long-range rocket, warning it would destabilize the region and further isolate Pyongyang from the world community.
The launch marks "yet another example of North Korea's pattern of irresponsible behavior," White House National Security Council spokesman Tommy Vietor said in a statement.
The move triggered plans for an emergency session on Wednesday of the UN Security Council, which has imposed sanctions against North Korea over its ballistic missile and nuclear programs.
North American Aerospace Defense Command (NORAD) officials said North Korea appeared to have successfully launched "an object" into orbit, marking a technological success for the hermit nation.
Washington and its allies have long insisted such launches are disguised tests for an intercontinental ballistic missile capable of carrying a nuclear warhead.
"Given this current threat to regional security, the United States will strengthen and increase our close coordination with allies and partners," Vietor said.
"North Korea is only further isolating itself by engaging in such provocative acts.
"Devoting scarce resources to the development of ballistic missiles and nuclear weapons has not brought it security and acceptance by the international community -- and never will," he added.
NORAD said early indications suggested that the first stage of the rocket fell into the Yellow Sea, and estimated that the second stage fell into the Philippine Sea.
"Initial indications are that the missile deployed an object that appeared to achieve orbit," it added. "At no time was the missile or the resultant debris a threat to North America."
A previous launch of the same Unha-3 rocket in April had ended in failure, with the carrier exploding shortly after take-off.
In 2006, the Security Council imposed an embargo against North Korea on arms and material for ballistic missiles and weapons of mass destruction.
It also banned imports of luxury goods and named individuals and companies as subject to a global assets freeze and travel ban.
In 2009, the Security Council imposed a ban on North Korea's weapons exports and ordered all countries to search suspect shipments.
According to Japanese reports, Japan, the United States and South Korea have agreed to demand the Security Council strengthen sanctions on North Korea to match those on Iran.
That would include increasing the list of financial institutions, entities and individuals subject to asset freezes.
Much will depend on the stance taken by UN veto holder China, North Korea's sole major ally and its biggest trade partner and aid provider.