United States footballer Megan Rapinoe and basketball star Sue Bird have announced their engagement, with Joe Biden among the first to offer congratulations.

Two-time Women's World Cup winner Rapinoe, who was hugely influential in last year's triumph at the finals in France, met Bird at the 2016 Olympic Games in Rio.

        View this post on Instagram                       A post shared by Sue Bird (@sbird10) on Oct 30, 2020 at 4:20pm PDT

They announced they were a couple in July 2017, and Bird has now posted a picture on Instagram of Rapinoe putting a ring on her left hand.

Speaking to ESPN three years ago, Rapinoe explained how she and four-time Olympic gold medallist Bird found love, saying: "We have a lot in common and just sort of clicked. I joke she is my number one go-to-for-advice person. She's just so level-headed."

Tennis great Billie Jean King sent warm wishes to the couple, with Chelsea Clinton also congratulating Rapinoe and Bird, as did football's US Women's National Team and the WNBA's Seattle Storm, Bird's long-time team.

US presidential candidate Biden wrote on Twitter: "Love will always win. Congratulations, @S10Bird and @mPinoe!"

Earlier this year, Rapinoe offered to be the running mate for Biden, the Democratic Party's candidate.

The 35-year-old has used her platform to speak out on societal issues including racism, homophobia and the gender pay gap.

She drew the ire of incumbent US president Donald Trump having said she had no intention of visiting him if the USA won last year's Women's World Cup.