The mining sector appears poised for a frantic year of dealmaking, following market speculation over a potential tie-up between industry giants Rio Tinto and Glencore.

It comes after Bloomberg News reported Thursday that British-Australian multinational Rio Tinto and Switzerland-based Glencore were in early-stage merger talks, although it was not clear whether the discussions were still live.

Separately, Reuters reported Friday that Glencore approached Rio Tinto late last year about the possibility of combining their businesses, citing a source familiar with the matter. The talks, which were said to be brief, were thought to be no longer active, the news agency reported.

Rio Tinto and Glencore both declined to comment when contacted by CNBC.

A prospective merger between Rio Tinto, the world’s second-largest miner, and Glencore, one of world’s largest coal companies, would rank as the mining industry’s largest-ever deal.

Combined, the two firms would have a market value of approximately $150 billion, leapfrogging longstanding industry leader BHP, which is worth about $127 billion.

Analysts were broadly skeptical about the merits of a Rio Tinto-Glencore merger, pointing to limited synergies, Rio Tinto’s complex dual structure and strategic divergences over coal and corporate culture as factors that pose a challenge for concluding a deal.

“I think everyone’s a bit surprised,” Maxime Kogge, equity analyst at Oddo BHF, told CNBC via telephone.

“Honestly, they have limited overlapping assets. It’s only copper where there is really some synergies and opportunity to add assets to make a bigger group,” Kogge said.

Global mining giants have been mulling the benefits of mega-mergers to shore up their position in the energy transition, particularly with demand for metals such as copper expected to skyrocket over the coming years.

A highly conductive metal, copper is projected to face shortages due to its use in powering electric vehicles, wind turbines, solar panels and energy storage systems, among other applications.

Oddo BHF’s Kogge said it is currently “really tricky” for large mining firms to bring new projects online, citing Rio Tinto’s long-delayed and controversial Resolution copper mine in the U.S. as one example.

“It’s a very promising copper project, it could be one of the largest in the world, but it is fraught with issues and somehow acquiring another company is a way to really accelerate the expansion into copper,” Kogge said.

“For me, a deal is not so attractive,” he added. “It goes against what all these groups have previously tried to do.”

Last year, BHP made a $49 billion bid for smaller rival Anglo American, a proposal which ultimately failed due to issues with the deal’s structure.

Some analysts, including those at JPMorgan, expect another unsolicited offer for Anglo American to materialize in 2025.

Analysts led by Dominic O’Kane at JPMorgan said the bank’s “high conviction view” that 2025 would be defined by mergers and acquisitions (M&A), particularly among U.K.-listed miners and global copper companies, was coming to fruition just two weeks into the year.

The Wall Street bank said its own analysis of the mining sector found that the current economic and risk management environment meant M&A was likely preferred to the building of organic projects.

Analysts at JPMorgan predicted the latest speculation would soon thrust Anglo American back into the spotlight, “specifically the merits and probability of another combination proposal from BHP.”

Prior to pursuing Anglo American, BHP completed an acquisition of OZ Minerals in 2023, bolstering its copper and nickel portfolio.

Analysts led by Ben Davis at RBC Capital Markets said it remains unclear whether talks between Rio Tinto and Glencore could result in a simple merger or require the breakup of certain parts of each company instead.

Regardless, they said the M&A parlor games that arose following merger talks between BHP and Anglo American will undoubtedly “start up again in earnest.”

“Despite Glencore once approaching Rio Tinto’s key shareholder Chinalco in July 2014 for a potential merger, it still comes as a surprise,” analysts at RBC Capital Markets said in a research note published Thursday.

BHP’s move to acquire Anglo American may have catalyzed talks between Rio Tinto and Glencore, the analysts said, with the former potentially looking to gain more copper exposure and the latter seeking an exit strategy for its large shareholders.

“We would not expect a straight merger to happen as we believe Rio shareholders would see it as favouring Glencore, but [it’s] possible there is a deal structure out there that could keep both sets of shareholders and management happy,” they added.

Analysts led by Wen Li at CreditSights said speculation over a Rio Tinto-Glencore merger raises questions about strategic alignment and corporate culture.

“Strategically, Rio Tinto might be interested in Glencore’s copper assets, aligning with its focus on sustainable, future-facing metals. Additionally, Glencore’s marketing business could offer synergies and expand Rio Tinto’s reach,” analysts at CreditSights said in a research note published Friday.

“However, Rio Tinto’s lack of interest in coal assets, due to recent divestments, suggests any merger would need careful structuring to avoid unwanted asset overlaps,” they added.

From a cultural perspective, analysts at CreditSights said Rio Tinto was known for its conservative approach and focus on stability, whereas Glencore had garnered a reputation for “constantly pushing the envelope in its operations.”

“This cultural divide might pose challenges in integration and decision-making if a merger were to proceed,” analysts at CreditSights said.

“If this materializes, it could have broader implications for mega deals in the metals [and] mining space, potentially putting BHP/Anglo American back in play,” they added.

— CNBC’s Ganesh Rao contributed to this report.