QPR will this morning submit an improved offer for Macauley Bonne and are also keen to bring in winger Andre Green.
Charlton rejected a previous bid for striker Bonne and insisted he is not for sale.
But Rangers are hoping a deal can be agreed for the 24-year-old, who scored 11 goals last season.
Green, 22, is a free agent, having recently left Aston Villa.
He has held talks with a number of Championship clubs.