Walt Disney Co and Twenty-First Century Fox Inc were sued for more than billion on Monday by casino operator Genting Malaysia Bhd, which accused them of abandoning a contract related to its planned construction of the first Fox-branded theme park.

Genting said “seller’s remorse” induced Fox, with Disney’s help, to breach its 2013 contract with Fox Entertainment Group to license intellectual property for Fox World, a proposed addition to its Resorts World Genting complex, an hour’s drive from Kuala Lumpur.

Disney did not immediately respond to requests for comment. Dan Berger, a spokesman for Twentieth Century Fox Film, one of the defendants, declined to comment.

The lawsuit was filed in the U.S. District Court in Los Angeles as Disney prepares to complete its .3 billion purchase of many Fox assets, expected in the first quarter of 2019.