US president Barack Obama and British prime minister Gordon Brown on Monday led the international community in condemning a defiant North Korea's "reckless" nuclear test that directly challenged the world as they sought a global "action" against Pyongyang.
Terming the test a "threat to international peace", Obama said: "these actions while not a surprise given the statements and actions to date, are a matter of grave concern to all nations".
North Korea's attempts to develop nuclear weapons, as well as its ballistic missile programme in "direct defiance" of the UN Security Council, constitutes a "threat to international peace and security," he said.
North Korea announced on Monday that it carried out a second and "more powerful" nuclear test, defying international pressure to rein in its nuclear programmes.
British premier Brown denounced North Korea's nuclear test as a "danger to the world" that will undermine peace prospects on the Korean peninsula.
"I condemn North Korea's nuclear test in the strongest terms as erroneous, misguided and a danger to the world," Brown said in a statement, adding that it will "undermine prospects for peace on the Korean peninsula and will do nothing for North Korea's security."
"The international community will treat North Korea as a partner if it behaves responsibly. If it does not, then it can expect only renewed isolation," Brown said.
North Korea's neighbours, South Korea and Japan too condemned Pyongyang's action.
Describing the test as a "serious threat to world peace," and an "intolerable provocative act," South Korea said it will cooperate with the international community to have the UN Security Council take "appropriate measures" against Pyongyang.
"The (South Korean) Government urges North Korea to abandon nuclear weapons and related programmes and return to the Nuclear Non-Proliferation Treaty as a responsible member of the international society," according to a statement issued by presidential Spokesman Lee Dong Kwan.
Japanese prime minister Taro Aso, who described the nuclear test as a "grave challenge" to the NPT said North Korea's act was "totally unacceptable."
"We are at an important juncture, when it is of utmost importance for the international community to respond in unity," Aso said.
He also said that Japan has already requested an urgent meeting of the UN Security Council to discuss the issue.
In Beijing, the chinese Foreign Ministry said it was "resolutely opposed" to North Korea's nuclear test.
China is North Korea's closest ally and the host of six-party talks aimed at the denuclearisation of North Korea that also include Japan, Russia, South Korea and the US.
French foreign minister Bernard Kouchner said that Paris "strongly condemns" the nuclear test by North Korea.
"We strongly condemn this," he said.
In Moscow, Russian foreign minister Sergei Lavrov said the North Korean nuclear test was a violation of the UN Security Council's resolution and a matter of "concern".
"Naturally, we are concerned at the reports about an explosion of nuclear device by DPRK," Lavrov told Vesti TV, but said details of the test would be known only after 'analysis of data'.