Game of Thrones season 7
Queen Cersei with Jamie Lannister Helen Sloan/HBO

After Cersei's coronation as the queen of the Seven Kingdoms, rumours swirled that her fate will be sealed by none other than her twin brother Jaime in Game of Thrones season 7. , who plays the King Slayer in the HBO blockbuster, has weighed in on the popular fan theory as 'valid'.

"I mean I don't think he — I'm just saying it's a valid theory. I can see it makes sense, it has a beautiful — it's a nice circle [that] they are born together in the womb and then he kills her at the end...It makes sense," he told Mashable.

As per GoT lore, Jamie previously killed the Mad King after the latter wanted to use the wild fire to kill his people. And considering Cersei's evil doings in season 6, in which she used the wild fire to create the deadly blast that killed Tommen's wife Margaery and rest of her enemies, possibilities are high that Jamie will avenge the suicide of his only living son.

Jamie, who adored his children, now has nothing to live for, except for his incestuous partner who is now the evil queen. But if fan theories turn true, history will repeat itself and Jamie will slay the queen again. His queen-slaying will also fulfil the prophecy of Maggy the frog, who claimed that the queen will lose her children and will be killed by her little brother. Coster-Waldau thinks the death of Jamie's last living children may force him to take the drastic step.

"You could say that could – that the motivation for doing that would be the same for killing Cersei," he aid and added "but I haven't seen anything yet before Season 7 that would make me believe that he was capable of doing that."

Game of Thrones season 7 will premiere on 16 July on HBO.

Game of Thrones
Actors Rory McCann, Conleth Hill, Iwan Rheon, Gwendoline Christie, Peter Dinklage, Nikolaj Coster-Waldau, Maisie Williams, Emilia Clarke, Sophie Turner and Kit Harington, celebrate winning best drama series for Game Of Thrones at the 68th Annual Primetime Emmy Awards Frazer Harrison/Getty Images