The experienced Cardiff Blues flanker will controversially take part in two ties for the Baa-Baas this summer, coming up against England on May 30 and Ireland on June 4.

Wales coach Warren Gatland made the decision to rest the forward for the summer tests, and as Williams lines up in Dublin, Gatland’s side will be gearing up to face world champions South Africa the next day.

But veteran Williams, capped 95 times by his country, insists there is no issue with his call up to the invitational XV and Gatland has giving him his blessing.

“I made Warren fully aware of the situation and he totally understands where I am coming from,” said Williams.

“At the end of the day this is just one more week of rugby at the end of the season and it won’t affect my summer.

“I will still be able to have four weeks off from rugby and on top of that a full nine weeks pre-season behind me before the season starts up again.

“This may well be the last opportunity I get in my career to represent the Barbarians and play alongside some of the best players in the world. It is always a huge honour.

“It won’t affect my preparations for next year at all.”