It may be a miracle North Korea has returned to the negotiating table over its nuclear weapons arsenal but Foreign Minister Julie Bishop isn't expecting major diplomatic triumphs from Tuesday's historic summit with the US.
US President Donald Trump and North Korean leader Kim Jong-un are scheduled to meet on Tuesday on Singapore's Sentosa Island.
The foreign minister has been hosing down Australia's expectations pointing out North Korea has previously made promises that it hasn't honoured and has signed agreements it's walked away from.
"I have been very sceptical all along, perhaps I should say I'm very cautious, because we've been down this path before," Ms Bishop said.
She acknowledged US President Donald Trump's "unorthodox approach" had disrupted the status quo and she hopes there will be verifiable concrete steps in the de-nuclearisation process.
"I want to be hopeful (but) I just don't think we should expect too much," Ms Bishop said.
Prime Minister Malcolm Turnbull has also warned of "false dawns" before on the Korean peninsula.
Australian National University professor Hugh White is optimistic the summit will produce a positive outcome mostly because it's still going ahead despite all the shenanigans in the lead up.
"Both sides have had a chance to size up the other and withdraw if they want to, it's been called off and put on again. Both sides appear to want to make it work," he told AAP.
Trump is seeking to persuade North Korea to dismantle all its nuclear weapons quickly and allow international inspectors in.
In return, North Korea could get relief from economic sanctions.
So far Kim has pledged to stop missile testing and has closed down a nuclear test site.
The North sees de-nuclearisation as a mutual task to be completed slowly over time.
Initially this might mean a cap on weapons numbers.
"Somewhere between doing nothing and doing everything lies the real world of negotiable outcomes," Prof White said.
He expects Trump to focus on North Korea's intercontinental ballistic missile program which is a direct threat to the US.
Pyongyang's longest-range intercontinental ballistic missile could in theory travel 13,000 kilometres. This covers most of the world except South America and Antarctica.
It would be significant if the summit results in a peace treaty formally ending the Korean War. The 1950-1953 conflict ended in a truce.
"That might sound like a formality but it could easily lead on to the actual normalisation (of relations) between North and South Korea," Prof White said.
There's a possibility the US could down the track reduce its military presence in South Korea.
"If (the summit is) successful it will make Trump look good in the short term and America look weaker in Asia in the long term," Prof White said.