Thomas, who is a former Heineken Cup winner, returns to the Premiership after previously having played with Bath two seasons ago and is the second new signing announced for the 2005-2006 Guinness Premiership season, following on from All Black Justin Marshall.

Thomas joined Cardiff Blues from Bath in the summer of 2003 and previously played for his home club of Bridgend. He has played at all levels for Wales from Wales Schools, Wales Students and Wales under-21, as well as playing in the senior sevens squad before he won his international cap as a replacement against South Africa in 1996. Thomas went on tour with Wales to North America in 1997 and South Africa in 1998. The back rower spent seven seasons at the Recreation Ground with Bath including featuring in the 1998 Heineken Cup winning side against Brive.

Commenting on his capture Director of Rugby Phil Davies said, "We are delighted to have signed Nathan and to see him return to the Premiership. He is an experienced back rower who will add a lot to our squad for next season having lost Alix Popham and Colm Rigney. He is also a very versatile player who can play in all three back row positions and we are very happy he has decided to join us."