South Korean billionaire Chey Tae-won has been instructed to pay his former spouse 1.38 trillion won ($1bn; £788m) in cash - marking the largest divorce payout in the nation's history.

This verdict arrives almost ten years after Chey's marriage dissolved following the revelation of his extramarital child.

The Seoul High Court's decision on Thursday affirmed that Roh So-young - Chey's partner for 35 years - was entitled to a segment of his corporate stocks.

Representatives for Chey, who leads the influential SK Group conglomerate, declared intentions to contest the ruling, alleging the court had accepted "Roh's unilateral assertions as facts."

The sum granted to Roh signifies a significant escalation from the 66.5bn-won settlement ordered by a lower court in 2022.

The previous family court had dismissed Roh's plea for a share of Chey's SK shares.

However, this stance was reversed by the High Court, which deemed the shares as joint assets.

In its verdict, the court stated that "it was reasonable to rule that, as his wife, Roh played a role in increasing the value of SK Group and Chey's business activity".

The court estimated Mr. Chey's fortune at approximately 4 trillion won, implying that Ms. Roh - the mother of Mr. Chey's three children - would receive an estimated 35%.

Furthermore, it determined that Ms. Roh had assisted in navigating regulatory obstacles for Mr. Chey's enterprise and that her father, former South Korean President Roh Tae-woo, had acted as a "protective barrier" for SK's former chairman, Chey Jong-hyon.

The court criticized Mr. Chey for displaying "no signs of regret for his immoral conduct during the trial... nor reverence for marital fidelity," stating that the new settlement considered Ms. Roh's suffering from her former husband's extramarital affair.

Mr. Chey's legal team contended that, instead of benefiting his business, his ex-wife's political affiliations had been detrimental.

Following the ruling, shares in SK Inc - a major producer of semiconductors globally, with interests in telecommunications, chemicals, and energy - surged by 9%.