"Ivanka Trump has been briefed on this, she’s been part of the team," Mnuchin said. "She had dinner with President Moon, they had a private discussion in advance about this occurring."
Ivanka Trump is in South Korea as part of the US delegation that will attend the closing ceremony of the 2018 Winter Olympics.
Earlier on Friday, Mnuchin announced the largest sanctions package that targets 27 entities, 28 shipping vessels and one individual for having participated in illicit trade with North Korea.
The sanctions impact an entities and shipping vessels from North Korea, China, Singapore, Taiwan, Hong Kong, Marshall Islands, Tanzania, Panama and Comoros, the Treasury Department said in a press release.