US President Barack Obama said the United States would strengthen its missile defence and help the world respond to the threat posed by North Korea, which defied the international community by conducting its third nuclear test on Tuesday.
In his state-of-the-union speech, Obama also urged Congress to pass laws to protect the country's critical infrastructure from cyberattacks, which are a growing concern to the economy and national security.
"America will continue to lead the effort to prevent the spread of the world's most dangerous weapons," Obama said in his speech. "The regime in North Korea must know that they will only achieve security and prosperity by meeting their international obligations.
"Provocations of the sort we saw last night will only isolate them further, as we stand by our allies, strengthen our own missile defence and lead the world in taking firm action in response to these threats."
On cyberthreats, Obama said America's enemies were "seeking the ability to sabotage our power grid, our financial institutions and our air traffic control systems. We cannot look back years from now and wonder why we did nothing in the face of real threats". He signed an executive order on cybersecurity that calls for voluntary reporting of threats to US infrastructure.
The National Institute of Standards and Technology now has a year to finalise a package of voluntary standards and procedures that will help companies address their cybersecurity risks.
Obama also pledged to pursue a trade agreement with the European Union, while at the same time completing discussions for a Pacific-region accord.
Additional reporting by Associated Press