LONDON (AFP) -- BHP Billiton on Monday hinted it could launch a hostile takeover bid for Anglo-Australian mining rival Rio Tinto after the latter turned down an offer worth 153 billion U.S. dollars (105 billion euros).

""Our sole objective is to tell people about this unique value proposition and get Rio Tinto to engage,"" BHP Billiton Chief Executive Marius Kloppers told analysts and reporters in a conference call when asked if his company would go hostile.
""What other things eventually are down the road I just wouldn't care to speculate today,"" he added.
BHP, the world's largest miner, on Friday launched a bid for Rio Tinto to create a 350-billion-U.S.-dollar behemoth, sending Rio's shares soaring to a new record high in Australian trading on Monday.
However, Rio Tinto has twice rebuffed approaches from BHP Billiton to discuss the offer on the grounds it is too low.
Rio said it was also focusing on finalizing its own 38-billion-U.S.-dollar takeover of Canada's Alcan -- already the biggest-ever acquisition in the global metals and mining industry.
A merger of the world's two largest mining firms has been seen as increasingly likely in the industry, which is booming thanks to unprecedented demand from China and India.
On Monday, BHP said a takeover of Rio would unlock 3.7 billion U.S. dollars of shareholder value annually. In a statement to the Australian Stock Exchange, BHP Billiton called the tie-up ""logical and compelling"".
The shareholder value would come over seven years from enhanced earnings and cost-savings, it said, citing the firms' overlapping presence in resource-rich areas such as Western Australia's Pilbara region.
BHP also said it planned to buy back 30 billion U.S. dollars of its own shares if its bid, worth 153.2 billion U.S. dollars, were successful.
""BHP Billiton firmly believes that the rationale for combining BHP Billiton and Rio Tinto is compelling due to the strategic fit, the expected synergies and the opportunity to create an organization without parallel,"" it said.
""This combination will unlock unique value for both BHP Billiton and Rio Tinto shareholders.""
BHP Billiton argues its offer of three of its shares for each Rio Tinto share represents a premium of about 28 percent to the combined market value in the three months to October 31.
BHP meanwhile downplayed the significance of competition hurdles, saying it saw no significant barrier to the deal succeeding and that any regulatory concerns could be addressed, anticipating nine to 12 months to gain approvals.
If Rio Tinto shareholders accept the offer, they will end up owning 41 percent of the combined group.
Rio Tinto shares soared to a new high in Australian trade on Monday of 149.99 Australian dollars (134.29 U.S.), before closing at 139.72 Australian dollars, up 6.7 percent.
BHP Billiton fell 77 Australian cents to 41.70 Australian dollars.