Wales star and qualified doctor Jamie Roberts believes the fall-out from the George North concussion controversy will contribute towards making rugby union a safer sport.

The game's governing body World Rugby has said Wales wing North should not have remained on the field after a clash of heads with team-mate Richard Hibbard during last Friday's RBS 6 Nations clash against England.

But World Rugby added that it accepts the Welsh Rugby Union's explanation surrounding the incident.

North appeared to suffer a momentary loss of consciousness after the 61st-minute collision with Hibbard. WRU national medical manager Prav Mathema subsequently admitted that had the second incident been seen by medics, then North would have been immediately taken off and replaced.

North left the field in the first-half after receiving an accidental boot to the head from England lock Dave Attwood, but he was able to continue after treatment.

World Rugby, meanwhile, has also announced that it will be "immediately investigating, evaluating and promoting the implementation" of new measures.

These are the practicality of television match official technology being expanded to identify head injuries as they happen on the field, all elite competitions being requested to provide pitch-side video for medical staff, and all elite tournaments encouraged to adopt the Rugby World Cup 2015 player welfare standards.

"It's unfortunate, that second incident," said Roberts, speaking at the Wales squad training base on Tuesday.

"I think all the protocols have been followed by the Union medical staff. It was unfortunate they didn't see it happen, the second one (incident).

"All the players trust the medical staff. They are a very experienced bunch, and we trust their calls. It was an unfortunate incident.

"A lot has been made of it, and rightly so.

"Concussion is a huge part of the game at the moment, and hopefully moving forward, the protocols that we put in place - from our side, there will be video replays now for the medical staff at home and away matches - are going to make the game safer for the players involved.

"Safety of the players is paramount.

"A lot has been made of this incident, but I think the medical team dealt with it fantastically well and did everything in their power and did everything right that they should have done."

As for World Rugby looking at possible TMO technology to assist in head injury situations, Roberts added: "You look back over the last 10 years at how referees have been able to have a video replay - whether a try has been scored or when certain things have happened - and medics haven't.

"I suppose that is a question that needs to be asked."

In a statement, World Rugby said it believed North should not have remained on the field following the second-half clash of heads, but added that it accepted the WRU's explanation that neither Wales' team medical staff nor the independent doctor had sight of the incident.

Northampton star North has started return to play protocols. Although he has shown no concussion symptoms at any point, he is being treated as such by Wales medics following their video reviews of the incident.

Wales resume their Six Nations campaign against Scotland at Murrayfield next Sunday, with head coach Warren Gatland due to name his starting line-up on Wednesday.

"George is completely symptom-free. He is going through the return to play protocol," Wales assistant coach Robin McBryde said.

"The medical team have already stated that had they seen it themselves then George would have been removed, and since then procedures have been put in place with regards to pitchside review or a video replay system for the medical team.

"This has been communicated to World Rugby in the hope that we can learn from this incident so that it does not happen again."

Wales prop Samson Lee was concussed during the England game and has also embarked on return to play protocols.

"All I can tell you is they (North and Lee) are undergoing the return to play protocol, and the time that takes, it takes. I cannot say any more than that," McBryde added.

"It's something we have got to take our time over, and if we have got to delay naming the team, we will do. We are not going to be silly about it."

World Rugby, meanwhile, said: "Following a full post-incident review, World Rugby believes that Wales player George North should not have remained on the field of play following a head impact in the 61st minute of the Wales versus England RBS 6 Nations match at the Millennium Stadium on Friday night.

"The World Rugby head injury protocol clearly states that a player should be immediately and permanently removed from the field of play where there are any visible symptoms or suspicion of a potential concussion.

"However, following thorough discussions and input from the expert independent Concussion Advisory Group, World Rugby accepts the WRU's explanation that neither the team medical staff nor the independent doctor had sight of the incident.

"World Rugby understands that the medics acted within the framework of information they had at the time, and would have taken a different course of action had they had direct pitchside visibility or access to the same broadcast footage seen by those watching on television.

"Player welfare is World Rugby's number-one priority, and the incident highlights the importance of ensuring that medical staff are given the best possible level of support to minimise the chance of a repeat incident and further enhance the protection and support of players."