Defender Tyrone Mings said the England players had decided as a group at half-time to continue the game, but Williams said they would be within their rights to down tools.

"What happened was a complete disgrace and England dealt with it quite well," Williams told the PA news agency at a McDonald's Fun Football Session in Cardiff.

"But a walk-off for me would be perfectly acceptable. You don't need that abuse at all.

"As players we understand that you're going to get booed or get a little bit of stick.

"But there's no reason why just because you play football you should have to deal with that (racist) abuse.

"If it was too bad then I'm taking my team out of the firing line – 100 per cent."

Bulgarian Football Union president Borislav Mihaylov resigned in the wake of the racist abuse aimed at England's players and UEFA has opened disciplinary proceedings against Bulgaria.

Under Article 14 of UEFA's disciplinary regulations which relates to racism, the punishment may be to order the BFU to play one match behind closed doors and issue a 50,000 euros fine (which equates to just over £43,500).

However, there is provision under Article 14, 'where circumstances of the case require it' to impose additional disciplinary measures such as ground closure for multiple matches, forfeiture of a match, points deduction or disqualification from the competition.

FIFA president Gianni Infantino wants to see worldwide life bans imposed on fans found guilty of racist abuse, but Williams does not believe that will eradicate the problem.

"People are getting away with it, but if you get a lifetime ban it doesn't really matter because the game is on the internet anyway," Williams said.

"It's a difficult one because you can punish a team when the team and the majority of fans haven't done anything wrong.

"Playing behind closed doors is no punishment at all if we're being honest.

"We've had so many cases over the years, including in the Premier League, that have not been dealt with properly.

"It's pretty obvious that more needs to be done to stop it. But it's a reflection of everyday life and football is just part of that.

"Maybe it will always be there, but until we educate people better it definitely will be."

:: Ashley Williams was speaking at one of McDonald's Fun Football Sessions, which introduces kids to the game for their first time. Sign up today and start your child's football journey – mcdonalds.co.uk/funfootball