The U.S. received a $2 million hospital bill from the North Korean government for the care of American Otto Warmbier, who fell into a coma for unknown reasons while he was imprisoned in the country before he died in the U.S. in 2017, Fox News has confirmed.

Pyongyang authorities insisted the U.S. envoy sent to retrieve the University of Virginia student sign a pledge to pay the bill before allowing Warmbier’s comatose body to return to the United States, the Washington Post reported Thursday. Sources familiar with the matter confirmed the bill and the amount to Fox News.

Citing two people familiar with the situation, the Post reported the envoy signed an agreement to pay the medical bill on instructions from President Trump. However, a source told Fox News the U.S. did not pay money to North Korea.

The White House declined to comment, with Press Secretary Sarah Sanders saying in a statement: “We do not comment on hostage negotiations, which is why they have been so successful during this administration.”