Williams, who will be 35 in September, and Peel are both to be rested, while Hook – arguably Wales’ most consistent performer during this season’s RBS 6 Nations campaign – will undergo shoulder surgery once the Ospreys’ Magners League title assault is over.

Newport Gwent Dragons forward Charteris is currently recovering from a neck problem, which means he will not be considered for summer duties by Wales boss Warren Gatland.

Gatland is due to name his squad on Sunday for the June 5 Springboks clash in Cardiff, which is followed by appointments with the All Blacks in Dunedin and Hamilton.

“We have some depth in these positions with the likes of Jamie Roberts, Andrew Bishop and Jonathan Davies playing well at the moment at centre,” said Gatland.

“We are okay in the second-row as well, and Sam Warburton has been pushing Martyn really hard for a back-row spot at Cardiff Blues, as well as at international level.

“South Africa in Cardiff, and then two Tests in New Zealand, means we have a tough summer ahead of us. But this is exactly the position we need to be in, and it will be perfect preparation for the World Cup.”

Hook could be sidelined for up to five months, which might mean him facing a fitness fight to be fit for Wales’ autumn Tests later this year.

But Gatland is in an upbeat mood ahead of the June challenges, which follow a disappointing season for Wales.

“Games don’t come much tougher than playing the world champion South Africans, and (Springboks coach) Peter de Villiers has a wide range of talent to choose from,” he added.

“Depending on what happens in the Super 14 competition, certain players will be ruled out.

“But we will be expecting the European-based players like Butch James to figure, and (Natal) Sharks players are likely to be available, so there will be World Cup winners throughout the squad.

“They are going to be strong, but it could also be a great day for Wales. If we could win that game it would be a great platform for our summer tour.

“As for New Zealand, we just need to believe in ourselves and perform like we know we can – then, we will have a chance.

“France won a game there (New Zealand) last year and Ireland ran them close as well, so we know it can be done.

“But we are also keen to familiarise the players with our (2011) World Cup venues and training bases.

“It’s not until I left New Zealand that I realised that it is such a difficult place to tour, and we want the players to have that experience, training at the same venues and staying in the same hotels as we will in 2011.”