Sept 21 (Reuters) - Rio Tinto Plc RIO.L :
* RIO TINTO - TO COMMENCE ADDITIONAL $2.5 BILLION SHARE BUY-BACK PROGRAMME, RETURNING PROCEEDS OF SALE OF COAL & ALLIED TO ITS SHAREHOLDERS
* RIO TINTO - CAPITAL RETURN PROGRAMME WILL BE EXECUTED THROUGH A COMBINATION OF AN OFF-MARKET BUY-BACK TENDER, TARGETING A$700 MILLION OF CO SHARES
* NEW ON-MARKET PURCHASES BY RIO TINTO PLC WILL COMMENCE ON 27 DECEMBER 2017 AND WILL BE COMPLETED NO LATER THAN 31 DECEMBER 2018
* RIO TINTO - BALANCE OF $1.9 BILLION OF ADDITIONAL FUNDS BEING ALLOCATED TO RIO TINTO'S EXISTING ON- MARKET PURCHASES OF CO ORDINARY SHARES OF 10P EACH
* MAXIMUM NUMBER OF SHARES THAT MAY BE PURCHASED BY RIO TINTO PLC UNDER PROGRAMME IS 100 MILLION