MELBOURNE (Reuters) -Global miner BHP Group and Canada-listed Lundin Mining will jointly take over developer Filo Corp for C$4.5 billion ($3.25 billion), the companies said on Monday, as they move to progress the South American projects.

BHP and Lundin will form a 50/50 joint venture to hold both the Filo del Sol and Josemaria projects around the Argentine-Chile border.

BHP and Lundin have offered C$33 per Filo share, reflecting a 12.2% premium to the Canadian copper miner's last close on Monday. Under the deal, BHP is expected to pay a total of $2.1 billion in cash.

Reuters reported on July 12 that Lundin and BHP were weighing a joint bid.

"BHP has been looking to bulk up their copper outlook. "We are still bullish on the outlook for copper, even though it has come off a long way, the medium term fundamentals remain positive," said analyst Baden Moore of CLSA.

The deal is demonstrating to BHP's shareholders that BHP has other strategies to build their copper exposure, although I don't think it means they have definitively walked away from Anglo," he added.

The deal comes as BHP in May walked away from a blockbuster $49 billion bid to take over Anglo American which rejected three proposed offers from its bigger rival over the course of six weeks, as it strove to beef up its copper holdings.

It comes as miners race to build out their pipelines of copper, a metal whose use is expected to underpin the energy transition. Shares fell 1% in a downbeat market.

The world's biggest miners are increasingly preferring to buy instead of building assets to grow, given rising costs for developing new mines and a blow-out in time lines for regulatory approvals.

($1 = 1.3854 Canadian dollars)

(Reporting by Melanie Burton in Melbourne and Rishav Chatterjee and Gursimran Kaur in Bengaluru; Editing by Alan Barona and Stephen Coates)