North Korea making 'fissile material', US Secretary of State admits

North Korea is still making the crucial and devastating ingredient required for atom bombs, the US Secretary of State has admitted.

Being questioned at a US Senate hearing, Mike Pompeo was asked if North Korea was continuing its nuclear weapons program.

"Yes, they continue to produce fissile material," Pompeo said.

Fissile material is the active ingredient in a nuclear weapon.

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But Pompeo argued that "progress is happening" with the US's push for denuclearisation.

"As far as the Trump administration's goals on North Korea are concerned, nothing has changed," he said.

"Our objective remains the final, fully verified denuclearisation of North Korea, as agreed to by Chairman Kim Jong-un."

Kim Jong-un agreed to "denuclearisation" in his summit with US President Donald Trump in Singapore last month.

But the failure to establish a firm deadline or definition for "denuclearisation" in the pair's 426-word agreement has allowed the regime enough wriggle room to continue its program.

Pompeo pledged to maintain tough international sanctions against North Korea despite efforts from Russia and China to water them down.

Earlier this month Trump reiterated his faith in Kim Jong-un via Twitter.

Seismic analysis from North Korea's nuclear tests have shown the country is capable of making 60-kiloton bombs.

The country has also developed an intercontinental ballistic missile (ICBM) capable of hitting any target in Australia.

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