Maisie Williams' mother is currently on social media gloating because she knows how Game Of Thrones will end.

Appearing on Jimmy Kimmel Live! the 20-year-old actress, who has been playing Arya Stark on the HBO fantasy series since its inception, said that she had given her mother the ultimate spoiler.

"I sent my mum the scripts," she said before revealing that she had initially taunted her.

When Kimmel asked whether she was allowed to give out such sensitive material she admitted that it may not have been a good idea.

"Probably not. They [producers] said 'don't give them to anyone,'" she said, before adding that she had created a monster.

"My mum is tweeting out 'I know the end of Game of Thrones.'"

Season 7 of the show suffered multiple leaks, and the most recent run of episodes was pirated over one billion times. It has been reported that producers have gone to great lengths to avoid leaks of the final season, which airs in 2019. But according to Williams filming several different endings is not a strategy.

This rumour was started by HBO Network president of programming Casey Bloys, but the British actress joked in response: "As we know, sometimes presidents don't always tell the truth."

Back in January, Williams took to Twitter to clarify reports that she had revealed details of the upcoming eighth season of Game of Thrones in an interview with Metro, which she said was false.

"This Game of Thrones release date 'quote' I've supposedly given is completely false and taken from an interview I did years ago," she said.