Scrum-halves Natasha 'Mo' Hunt and Ella Wyrwas have been awarded England contracts.
Hunt, 34, debuted against USA in 2011 and has featured 67 times for her country to date over the past decade, winning the Rugby World Cup in 2014.
Head of women's performance, Charlie Hayter, said: "Mo's mindset to keep improving and push herself has seen her play some of the best rugby of her career over the past year.
"She suits the way we want to approach the game and her experience is invaluable. During the recent WXV campaign, she enhanced the Red Roses culture and has bought into what we are aiming to achieve on and off the field as we embark on our new journey."
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Wyrwas' six England caps have all been earned in a stellar 2023 which has seen the 24-year-old contribute to a Women's Six Nations Grand Slam and success in the inaugural WXV competition.
Hayter added: "Ella has taken the international opportunities during the 2023 Six Nations and this year's WXV with both hands.
"She has brought her club form into the Red Roses environment and continues to grow and develop. We are looking forward to working with Ella as a centrally contracted player and continue to see her exciting talent evolve."
Hunt and Wyrwas will reunite with their international team-mates in January 2024 as John Mitchell leads his first training camp as head coach ahead of the Women's Six Nations.
Following last season's record-breaking crowd against France at Twickenham Stadium, the Red Roses will once again host a standalone fixture at the home of English Rugby. Ireland are the visitors on Saturday April 20.
Two rounds prior, England Women head to Ashton Gate in Bristol to take on Wales on Saturday March 30.