Speaking to EnergyNewsPremium on the sidelines of the Excellence in Oil and Gas Conference in Sydney, Weller said PNG was one of the few places where large companies could get their foot on opportunities with sufficient scale.
"I think it's the fact that there's simply a dearth of opportunities for companies to get large-scale resources elsewhere," he said.
"That's why you're seeing interest in deepwater west Africa, the Santos Basin … which are very expensive plays to pursue.
"It's a cliche but there is no cheap oil anymore. It has to be true before it becomes a cliche, though.
"You look at PNG and it's relatively underexplored as a basin and you're seeing a lot of gas there, and it's an example of an area that a big oil company may look to invest and acquire assets there."
Weller also dismissed suggestions that the PNG political situation, which has drawn subdued threats of sanction by Australia, would have an impact on investment decisions.
"It's one of the nuances of the oil and gas business that there seems to be a lot of oil and gas in places that are less than ideal geopolitically, but it's always been a fairly challenging political environment," he said.
"I think people would look at PNG with a full idea of the political situation there but I don't see that putting off anybody.
"I mean, you look at the Exxon project and what that's going to do to the economy, it's going to absolutely transform that country. I think if you take the long-term view, it's much easier to see that there's likelier to be a more stable environment going forward."
Political instability hasn't stopped the private sector from investing in the country, with the news of Mitsubishi farming into nine of Talisman Energy's permits for $US280 million ($A266.6 million) last month proving the point.
Meanwhile in Australia, Weller said regulatory wrangling in NSW hadn't stopped UBS from labelling NSW a promising M&A prospect.
The NSW government has drawn criticism from the petroleum industry for what it sees as burdensome regulations including a moratorium on fraccing and its recently announced strategic land use review.
As part of the draft review, over 1.3 million hectares of high-value agricultural land have been identified in the two regions as part of the review, and if a coal seam gas exploration permit comes within 2km of one of these areas, it will have to undergo a gateway process before being signed off.
An independent mining and coal seam gas gateway panel would be established to consider gateway certificate applications, leading to concerns in the industry that there may be a duplication of processes.
However, Weller pointed to Santos' investment in Eastern Star Gas last year as evidence that M&A activity will occur, no matter the regulatory environment.
"UBS certainly sees ongoing consolidation in that sector, but people are focused on the opportunities in Queensland … Australia is a place with huge growing domestic demand and if you look at NSW, it imports 95% of its gas," he said.
"I think there's quite a compelling story for coal seam gas in NSW once there's more clarity on the approvals process and in the background you'll see a ramp-up in activity. For all the issues NSW has, it didn't stop Santos making a huge investment in Eastern Star Gas."
On the broader coal seam gas front, he said majors would continue to "position their chess pieces on the board" as project delivery for LNG projects drew nearer, and this would involve looking at farm-ins and acquisitions in places where they hadn't been considered before.
"It could be that some of the project owners want to enhance their resources, because I think a lot of it has been centred around the sweet spots, but now they're going to some of the areas where they wouldn't look before because they simply need to prove up the resource," Weller said.
On the shale front, Weller said to expect more joint ventures to be formed in remote basins, pointing to historical patterns found in the early days of US shale and the formative stages of the CSG industry in Australia.
"You'll see a lot of joint ventures in the shale space. If you look at the M&A activity in the shale plays in the US and the early CSG plays in Queensland there was a trend of joint ventures, and once there was due diligence by stealth, then there was more confidence in the acquisitions side" Wellers said.
"So I also think there'll be a lot more interest in basins outside what you'd call the ‘traditional' basins.
"In the Canning Basin, we're big believers in what Buru is doing and their story, and I think you'll see a higher level of interest in companies such as Buru and you will see Conoco take a view on what they're doing with New Standard."
He also raised the spectre of increased international investment in the space.
"If you look at other majors around the world with shale in their portfolio, I think they'll look to transplant that know-how into Australia," Wellers said.
"It wouldn't be hard to look at the companies that have positions in US shale like Total and some of the Indian, Korean and Chinese players and think they'll be seeing an opportunity in Australia.'
First published in fellow Aspermont publication EnergyNewsPremium.net yesterday.