Global miner Rio Tinto on Thursday completed its acquisition of Canadian uranium junior Hathor Exploration as the company bets on the sector recovering from the Fukushima nuclear disaster.

Rio said it had compulsorily acquired the remaining 7.9 million shares not voluntarily offered after it made a Aus$623 million (US$642 million) takeover bid in October.

The miner offered Can$4.70 (Aus$4.48) a share to secure Hathor, trumping North American-focused uranium company Cameco's Can$4.50 a share bid.

"Rio Tinto is now the registered holder of 135,290,661 Hathor common shares, representing 100 percent of the outstanding Hathor common shares on a full-diluted basis," Rio said in a statement.

Hathor is based near western Canada's Athabasca Basin and supplies about a fifth of the world's uranium.

Uranium prices have suffered since the Fukushima disaster in Japan when the plant's reactors were crippled by an earthquake and tsunami on March 11 last year.

But many analysts are tipping a recovery with demand driven by China and India as they look to boost their nuclear power capabilities.