British and Irish Lions boss Warren Gatland has been given permission to speak to head coaches from home unions about joining the tour of South Africa.

Gatland has spoken to the various chief executives, and will make appointments in the coming months.

"The international coaches are a little bit easier [than club coaches] in terms of being available," Gatland said.

"The CEOs have generally been incredibly supportive and pretty positive about giving us the best chance of being successful.

"We've had those conversations and it's now about talking to potential coaches and trying to put a coaching team and backroom team together."

Gatland was the last head coach of a British or Irish national team to go on a Lions tour - when as Wales boss he joined Sir Ian McGeechan's staff in 2009.

He feels the extra responsibility coaches such as Townsend and Farrell have with their countries does not preclude them from being involved in South Africa next summer.

Farrell has twice worked with Gatland, as defence coach in Australia in 2013 and New Zealand in 2017, but he has since stepped up to replace Joe Schmidt as Ireland head coach.

Townsend, a hero as a player with the Lions in 1997, has yet to tour as a coach, although he was approached by Gatland about a supporting role in New Zealand in 2017.

"Having spoken to some people who have been there in the past, they just say how invaluable the learning perspective in terms of going on a Lions tour, what you learn and bring back, probably outweighs so much about going on [a normal international] tour," he added.

"Sometimes a country going on [a summer] tour, they are going to smaller nations, and it's a chance to develop some of the other coaches from a leadership perspective as well."

Gatland also believes that coaching the Lions against the Springboks will provide priceless experience before the Rugby World Cup in France in 2023.

"It is incredibly tough, it is the hardest thing you will ever do as a coach or as part of the medical or strength and conditioning team, because it is just relentless, every day preparing two teams," he explained.

"There is no respite, but what you bring back from that, what you learn from the players and from the other coaches, playing against the world champions, there is so much of an upside that can be so beneficial for those international coaches two years out from a World Cup."