Manchester City and England forward Raheem Sterling has said clubs should be given an automatic nine-point deduction and ordered to play three games behind closed doors if their supporters take part in racist behaviour.

Authorities must adopt radical changes to tackle issues, Sterling said, after signing a manifesto that calls for consistent and suitable punishment for racist and discriminatory behaviour.

"I'd call for an automatic nine-point deduction for racist abuse," he wrote in a column for the Times. "It sounds harsh but which fan will risk racist behaviour if it might relegate their team or ruin their title bid?

"The club should have to play three games behind closed doors. That way, they lose revenue as a direct consequence of racist behaviour."

Sterling joined a number of professionals and clubs in endorsing the manifesto which also seeks more black and minority ethnic people in senior positions in football and no sanctions for players walking off the pitch if they encounter racism.