Former US secretary of state Hillary Clinton says the United States must remain a Pacific power, despite efforts at diplomacy in Korea.

On her first visit to Australia since losing the 2016 US presidential election to Donald Trump, Ms Clinton said the world will be better off if the US is an open, engaged and optimistic player in Asia.

AAP

She said that meant pursuing a purposeful engagement with China and using a steady hand in North Korea.

Ms Clinton warned there needed to be concrete concessions from North Korean leader Kim Jong-un.

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"I am very hopeful to see the diplomacy in Korea but we have to remain clear-eyed about how hard these negotiations will be and how often in the past North Korea has broken promises," she told a function in Melbourne on Thursday night.

"So we should be careful not to confer too much prestige or legitimacy on Kim Jong-un without seeing concrete concessions, let alone making concessions of our own.

"It's crucial that US troops remain on the Korean Peninsula and that the United States remains a Pacific power."

Russian influence

Clinton says Russia is still trying to turn Americans against each other.

Ms Clinton again warned that China's efforts to gain international power were an urgent problem.

Ms Clinton said the forces at work during the 2016 US presidential election, which she lost to Donald Trump, were still around.

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She said the Russian interference was more than alarming.

"It is a clear and present danger to democracy," Ms Clinton told an event in Melbourne on Thursday night.

"The Russians are still playing on anything and everything they can to turn Americans against each other.

"This is bigger than one candidate, one election or even one country."

Before being joined on stage by former prime minister Julia Gillard, Ms Clinton also said the only way to get sexism out of politics was to get more women into politics.