World Rugby investigating alleged racist abuse directed at England's Tom Curry

England had until Monday to lodge a complaint with the citing officer after Curry claimed he had been the victim of a discriminatory remark in Saturday's 16-15 World Cup semi-final defeat by the Springboks.

Curry claimed to referee Ben O'Keeffe in the second quarter of the Stade de France clash that he had been called a "white c***" by Mbonambi.

"World Rugby takes all allegations of discriminatory behaviour extremely seriously," a statement read.

"We can confirm that we are formally reviewing the allegation made by England’s Tom Curry in relation to the use of discriminatory language during the England versus South Africa Rugby World Cup 2023 semi-final on Saturday.

"World Rugby will not be making further comment until the conclusion of the process."

Follow all the Rugby World Cup fixtures in our live score centre

If World Rugby's inquiry triggers disciplinary proceedings they are likely to fall under the banner of 'bringing the game into disrepute', which can result in a range of sanctions including a suspension and/or a fine.

England have declined to make any comment on the incident but South Africa began their own investigation on Sunday.

"We are aware of the allegation, which we take very seriously, and are reviewing the available evidence. We will engage with Bongi if anything is found to substantiate the claim," an SA Rugby statement read.

When asked after the match if Mbonambi had said something he should not have done, Curry replied "yeah", although he declined to reveal the content of the remark.

WATCH: Selected matches will also be available on SABC Sport.com's live streaming channel

Mbonambi, who took over as captain once Siya Kolisi had been replaced, refused to shake Curry's hand at the end of a dramatic clash in Paris that was won by Handre Pollard's penalty after 78 minutes.

England head coach Steve Borthwick declined to speak about Curry's allegation.

"The situation around that is that I'm not going to comment on anything regarding that incident," Borthwick said.

READ MORE: Manie Libbok all class after early substitution: 'I am stoked for the guys'