Rangers have now signed him for an undisclosed fee on a three and a half year contract.
"Everyone knows QPR are my club and I'm delighted to be back here. The club are really going places and I'm just delighted to be part of what we hope will be a very successful chapter in its history," he told Rangers' official website.
"I feel as though I am getting back to my best and I can't wait for the second half of the season."
Rangers boss Paulo Sousa added: "Lee is an integral part of our future plans and we are delighted to have him here on a permanent contract. He's proven at this level, has great quality and gives us excellent options in the attacking third of the pitch."