Australia's Prime Minister Anthony Albanese and his Papua New Guinean counterpart James Marape are expected to sign a document to progress a defence treaty between the two countries when they meet in Port Moresby this week.
Mr Albanese will fly into PNG on Thursday for a two-day visit, after he was forced to delay a planned trip in December when he tested positive for COVID-19.
PNG raised the issue of signing a security deal when Australia's foreign minister visited the country in August.
"There will be a document put forward that both parties will agree to on Thursday," PNG's Foreign Affairs Minister Justin Tkatchenko said.
There have been meetings between PNG and Australian officials in recent weeks to discuss the wording of the document.
The ABC understands the document won't be the final treaty, which is still being discussed and finalised.
The document is expected to be signed after Mr Albanese and Mr Marape hold a one-on-one meeting on Thursday, where a range of issues are set to be discussed.
It's also expected that Australia will announce plans to open a visa processing office in PNG, as the applications are currently processed in Fiji.
The difficulty and delays many Papua New Guineans face when applying to visit Australia is a long-standing frustration for the country.
Mr Tkatchenko said regional security will be an "important" topic of discussion during the visit.
"Strengthening our security in the region (is) very important, making sure our region is secure," he said.
"And our traditional partners have always been Australia, New Zealand and the United States – and now looking at Indonesia as well, as we share the biggest border for Papua New Guinea."
Mr Tkatchenko said it was "interesting to note" that Australia already had a defence treaty with Solomon Islands and with Indonesia.
"For some reason, we haven't come together to have one with Australia and Papua New Guinea, maybe they feel that we're comfortable enough we don't need one.
"But now with the issues happening in our region and looking at the security side of things, this has now come to the table."
Australia's Defence Minister Richard Marles has previously said while China forms part of a "challenging and complex strategic world" it was not the main driver behind the bid to strengthen security ties with PNG.
Mr Marape has repeatedly said the country will continue to maintain its "friends to all, enemies to none" stance amid the rising geopolitics.
While it has long-standing defence relationship with Australia, China is PNG's biggest trading partner.
PNG downgrades presence in Taiwan
The Papua New Guinean government has recently decided to close its trade office in Taiwan, but says the decision hasn't been made as a concession to China.
Mr Tkatchenko said the decision came after a yearlong analysis of the office to see if it was economically viable to keep it open.
"We've come to conclusion that the office was no longer needed."
The office will be closed and replaced with a downgraded presence, called the PNG Taipei Economic Office, run by a "business liaison official".
He said the Taiwan Cultural Office in PNG would also be renamed, as the Taipei Economic Office.
"This is all to work together, not only for the benefit of trade and work with Taipei but also to work together with our Chinese counterparts.
"Since 1975, we have always supported the One China Policy, and we will continue to do so."
Only 14 countries in the world recognise Taiwan and have official embassies there. Dozens of other countries that have diplomatic ties with China maintain trade or unofficial offices in Taipei.
Papua New Guinea was among a very small handful of countries in the world that had "Taiwan" in the name of its unofficial office. Most countries avoid it because of opposition from China.
Mr Tkatchenko emphatically replied "no" when asked if China had requested PNG make the changes.
He said they hadn't had a response from Taiwanese officials yet, but said the decision was "pretty fresh".
He also denied the move was a way to appease China, as PNG moves to strengthen security ties with Australia.
"This has been going on even before I was the foreign affairs minister, they were looking before about whether to close it down, and when I came in, we were looking at all missions throughout the world, whether they should continue or not."
PNG has been struggling to pay the bills of its embassies and outposts around the world, and more closures are expected to be announced.
"Looking at all the statistics and all the rest of it coming from Taipei, Taiwan, it was not producing anything that we could justify the amount of funding we were spending to keep that office open."
Mr Tkatchenko also made reference to the behaviour of staff based in Taiwan, including an officer who publicly assaulted his own wife and a bystander, and who had previously been arrested for drink driving.
"We were completely embarrassed and ridiculed by the behaviour of certain officers who were running that trade office last year and they were all called back immediately."
He said the staff had made PNG look "absolutely stupid in the eyes of the world".
