Williams has been brought in to replace injured hooker Bennett

They replace injured Mark Jones, Kevin Morgan, Huw Bennett and Chris Wyatt.

Michael Owen returns to the 31-man party after missing the World Cup because of injury while Colin Charvis retains the captaincy.

"We are happy with the form of all the players and the more competition we have the better it is," said Hansen.

Hansen added: "The process has been made more difficult than normal due to the number of players who have been in good form throughout the regions.

"But rather than seeing this as a negative we look at that as a positive."

I'm very disappointed by the omission of Barry Davies From Cymraeg Janner Have your say on Scrum V

Seven of the Llanelli Scarlets side, who advanced to the Heineken Cup quarter-finals, have been included in the squad.

Match report: Northampton 9-18 Scarlets

Hansen, who will quit his Welsh post when his contract ends at the end of April, is determined to build on Wales' promising performance at the World Cup, where they reached the last eight after some battling performances.

Wales kick off their Six Nations campaign on 14 February against Scotland.

Wales squad:
Backs: Craig Morgan (Cardiff Blues), Jamie Robinson (Cardiff Blues), Rhys Williams (Cardiff Blues), Garan Evans (Llanelli Scarlets), Gareth Thomas (Celtic Warriors), Mark Taylor (Llanelli Scarlets), Tom Shanklin (Cardiff Blues), Sonny Parker (Celtic Warriors), Iestyn Harris (Cardiff Blues), Ceri Sweeney (Celtic Warriors), Stephen Jones (Llanelli Scarlets), Dwayne Peel (Llanelli Scarlets), Gareth Cooper (Celtic Warriors), Shane Williams (Neath-Swansea Ospreys), Hal Luscombe (Newport Gwent Dragons)

Forwards: Jonathan Thomas (Neath-Swansea Ospreys), Martyn Williams (Cardiff Blues), Colin Charvis (Tarbes - captain), Dafydd Jones (Llanelli Scarlets), Alix Popham (Leeds Tykes), Michael Owen (Newport Gwent Dragons), Gareth Llewellyn (Neath-Swansea Ospreys), Robert Sidoli (Celtic Warriors), Brent Cockbain (Celtic Warriors), Gethin Jenkins (Celtic Warriors), Adam Jones (Neath-Swansea Ospreys), Duncan Jones (Neath-Swansea Ospreys), Iestyn Thomas (Llanelli Scarlets), Robin McBryde (Llanelli Scarlets), Gareth Williams (Cardiff Blues), Mefin Davies (Celtic Warriors).