Malcolm Turnbull and Theresa May say China is the one country that has the ability to "bring the North Korean regime to its senses" and stop its nuclear missile program.
After a meeting at 10 Downing Street in London on Monday the two prime ministers told reporters their aim was the denuclearisation of North Korea.
Ms May said the UK had the same approach as Australia and believed China "was the country with the greatest possible leverage on North Korea".
She said that was the message she had given to Chinese President Xi Jinping at the recent G20 summit in Hamburg.
Mr Turnbull said China had the ability "to impose huge economic pressure on North Korea, and they should do so".
He said China was the only country that could "bring the North Korean regime to its senses without some form of military intervention".
North Korea's recent successful test firing of what is believed to an intercontinental ballistic missile has heightened global tensions over the regime's weapons program.
