Global miner Rio Tinto wrapped up one of the world's biggest rights issues on Friday, saying its Australian shareholders had taken up 94.76 percent of their entitlements to the new shares.

On Thursday, UK shareholders had taken up 96.97 percent of the deeply discounted, fully underwitten $15.2 billion rights offer, the fifth-biggest on record, putting the indebted Anglo-Australian group on a firmer financial footing.

The issue also marks a bonanza for the banks that underwrote it: Credit Suisse , J.P. Morgan Cazenove , Macquarie , Deutsche Bank , Morgan Stanley , RBS and Societe Generale .

The underwriters of the two legs of the rights issue were paid a 2.75 percent fee, or around $420 million in total, and are now also making a substantial extra profit by selling the small portion of shares that were not taken up by existing investors.

In the UK, banks sold the rump on Thursday at 21 pounds, a 50 percent profit on the London rights-issue price. The stock closed in London on Thursday at 20.35 pounds.

In Australia, banks will be looking on Friday to offload about 7.87 million shares, worth about A$407 million ($324 million) at Thursday's closing Australian share price of A$51.75.

Rio Tinto's Australian shares have been halted from trade pending the sale of the rump Australian stock.

Rio needed to raise the money to cut a $38 billion debt mountain it accumulated when it bought Canadian aluminum group Alcan at the top of the commodities market in 2007, an acquisition that opened one of the 136-year-old firm's darkest chapters.

Rio Tinto fell prey to an aborted takeover bid by rival BHP Billiton then briefly fell into the arms of its major shareholder, Chinese state-owned aluminum group Chinalco, before finally calling off the $19.5 billion Chinalco deal.

In the end, encouraged by a share-market rally and its investment banks, Rio Tinto opted for the rights issue and a cost-cutting iron ore joint venture with BHP Billiton.

But analysts said the mining giant still needs to sell non-core assets to pay down the $38 billion debt it took on to buy Canadian aluminum maker Alcan in 2007.

(Reporting by Mark Bendeich and Denny Thomas; Editing by James Thornhill)