Lewis, who has played 42 games for the region, has signed a two-year deal that runs until the end of the 2015/16 season.
He commented: “I am 100 per cent committed to the Ospreys and I’d like to apologise for any confusion caused by recent statements which coincided with a brief period of uncertainty on my part.
“However, I have signed a two-year contract to stay here at the Ospreys and I look forward to continuing to represent my home region as I continue to develop on and off the field.”