LONDON (Reuters) - Global mining group Rio Tinto <RIO.L> is in talks over a 2 billion pound ($3.2 billion) bid for Australian rival Riversdale Mining <RIV.AX>, British newspaper The Sunday Telegraph reported.

The British newspaper, citing unnamed sources, said Rio was bidding around A$15 per share for Riversdale, whose shares closed at A$14.10 on December 3.

The Sunday Telegraph said it was not certain a deal between the two companies would be completed.

A Rio Tinto spokesman in London said the company did not comment on market speculation.

Riversdale's major shareholders include Tata Steel <TISC.BO>, Brazilian steelmaker CSN <CSNA3.SA> <SID.N> and China's Wuhan Iron & Steel Corp <600005.SS>.

Riversdale has potentially lucrative assets in Africa and the company announced a coal discovery in Mozambique in October.

($1=.6338 Pound)

(Reporting by Sudip Kar-Gupta; Editing by Karen Foster)