Rio Tinto, the mining company, will pay $430m in fees associated with its $15.2bn rights issue, pushing the costs associated with its recent fundraising attempts to more than $625m.

Rio launches its fully underwritten 21-for-40 rights issue today, two weeks after dropping its campaign to raise $19.5bn from Chinalco, the Chinese state-owned mining group, and incurring a $195m break fee.

In addition to paying the break fee and rights issue fees, Rio will have incurred costs, not yet released, of pursuing the Chinalco deal from February until May.

The sum of these transaction costs is thought to be slightly less than $800m. Before 2010, Rio must repay $18bn in debt relating to its 2007 purchase of Canadian aluminium producer Alcan.

Rio also paid $270m to defend itself from BHP Billiton's hostile bid, which it dropped in November 2008.

One institutional investor in Rio, speaking on June 5 when Rio dropped the Chinalco deal, said the fees racked up by the company in the past year were a small price to pay for it to arrive at its latest fundraising plan.

The plan anticipates $14.8bn in net proceeds from the rights issue plus $5.8bn that BHP Billiton, a rival blue-chip miner, will pay Rio to participate in an Australian iron ore joint venture outlined by the two companies.

Echoing top Rio executives' defence of the company's shift in fundraising strategy, the institutional investor said the Chinalco deal had been the right option in February's depressed market, whereas the rights issue was the correct option in June, when financial and commodity markets had improved.

The rights issue prices 524.5m new London-listed Rio shares at £14, compared with yesterday's closing price of £28.29.

The proceeds will slash Rio's net debt, which stood at $37.8bn on March 31.