Joe Biden has waded into the dispute between the US women's national soccer team (USWNT) and US Soccer, tweeting that the players should not "give up this fight" for equal pay and threatening to withdraw funding from the governing body should he win the White House in November.
On Friday, US district judge R Gary Klausne threw out the players' unequal pay claim, which was filed in March 2019 by 28 members of the USWNT seeking equal pay and treatment, in addition to damages of $66m including back pay.
The group, which included some of the best players in the world such as Megan Rapinoe, Alex Morgan and Carli Lloyd, also sought compensation for any player who has appeared for the US since February 2015.
"Don't give up this fight," Biden wrote on Twitter on Saturday. "This is not over yet."
The presumptive Democratic candidate for president then turned his attention to the governing body.
"To US Soccer: equal pay, now," he wrote. "Or else when I'm president, you can go elsewhere for World Cup funding."
On Friday, Molly Levinson, spokeswoman for the women's players, said: "We are shocked and disappointed with today's decision, but we will not give up our hard work for equal pay.
"We are confident in our case and steadfast in our commitment to ensuring that girls and women who play this sport will not be valued as lesser just because of their gender."
Klausne said the USWNT players had rejected a chance to be paid under the same terms as their male counterparts.
"The history of negotiations between the parties demonstrates that the WNT rejected an offer to be paid under the same pay-to-play structure as the MNT, and the WNT was willing to forgo higher bonuses for benefits, such as greater base compensation and the guarantee of a higher number of contracted players," he wrote.
The judge did, however, allow allegations that the USWNT were subject to discriminatory working conditions, receiving inferior travel, accommodation and medical treatment compared to the men. Those claims will now go to trial in federal court next month.
The US won the Women's World Cup last summer, retaining a title they won in 2015. The US men's team, who have supported the USWNT lawsuit, failed to qualify for the 2018 World Cup.
On Thursday, Rapinoe appeared with Biden and his wife, Jill Biden, in an Instagram Live event.
"I don't want to put you on the spot," the player said. "I think I could still play soccer and do this. But if you need a vice-president, I'm just saying I'm available for an interview. We can talk logistics and the details. Put it on your list."
Biden has promised to pick a woman as his running mate. Rapinoe, he said, "would have to take a pay cut to become vice-president".
"You know I'm not into that," she said.