Dan Lydiate, Tom James and Gareth Anscombe are among 13 players released by Wales to play for their regions.
Wing James started against Ireland and Scotland, while flanker Lydiate made appearances off the bench.
Full-back Anscombe missed the game in Ireland with injury but was a second half substitute in the 27-23 win over Scotland in Cardiff.
Welsh squad players based in Wales do not have to be released during the Six Nations Championship.
With the international tournament taking a break, all four Welsh regions are in action.
|Ospreys: Paul James, Aaron Jarvis, Dan Lydiate, James King|
|Cardiff Blues: Kristian Dacey, Josh Turnbull, Lloyd Williams, Cory Allen, Tom James, Gareth Anscombe, Alex Cuthbert|
|Newport Gwent Dragons: Hallam Amos|
|Scarlets: Aled Davies|
On Friday, 19 February Ospreys play Edinburgh while the Dragons are away to Benetton Treviso.
Saturday sees the Blues at home to Leinster and Scarlets travel to Ulster on Sunday.
Squad players based outside Wales have already been released to their clubs.