Saudi Arabia’s Crown Prince Mohammed bin Salman extended “personal mediation efforts” to facilitate the release of American basketball star Brittney Griner in a Russia-US prisoner swap, the kingdom’s foreign minister said on Thursday.

Washington has denied any mediation, saying the talks were between the United States and Russia, after a joint Saudi-UAE statement that said the president of the United Arab Emirates and Prince Mohammed led mediation efforts.

“I am aware of his highness’s personal efforts in relation to the basketball player and his engagement and personal intervention to facilitate this release,” Prince Faisal bin Farhan told reporters in Riyadh. “As for what others say, I cannot comment on that.”

The swap involving Griner and Russian citizen Viktor Bout took place at an airport in the UAE capital Abu Dhabi.

Saudi Arabia had scored a diplomatic victory in September by securing freedom for foreign fighters captured in Ukraine, at a time of tension between Riyadh and Washington whose ties have been strained over human rights, oil supplies and Russia.

Riyadh has resisted Western pressure to help isolate Russia, a fellow OPEC+ oil producer.

Prince Faisal, at a news conference during a visit by China’s president to the kingdom, said Saudi Arabia does not believe in choosing sides, and sought to cooperate with all economic powers including rivals the United States and China.