The 40-year-old popstar was walking the red carpet at the Latin Grammy awards on November 18th when she was asked by a reporter if she had been in touch with Britney.
Her publicist quickly interjected and pulled Christina away to prevent her answering the question saying “No, I'm sorry, we're not doing that tonight, thank you though, bye."
As she walked away, Christina looked back and said "I can't, but I'm happy for her."
Taking to Instagram Stories, Britney shared a clip of the interview and hit out at Christina for not talking about her conservatorship.
“I love and adore everyone who supported me, but refusing to speak when you know the truth is equivalent to a lie,” she said.
“13 years being in a corrupt abusive system yet why is it such a hard topic for people to talk about? I’m the one who went through it all.
“All the supporters who spoke up and supported me, thank you… yes I do matter.”
Despite the bitterness, Aguilera previously shared her support for Britney on Twitter.
In June, she shared a snap of the pair as kids and said: “These past few days I’ve been thinking about Britney and everything she is going through.
“It is unacceptable that any woman, or human, wanting to be in control of their own destiny might not be allowed to live life as they wish.”
After slamming Christina for keeping mum, Britney went on to share praise for Lady Gaga for speaking about conservatorship while on a press tour for her new film House of Gucci.
“Thank you Lady Gaga for genuinely taking your time to say something so kind,” Britney said.
“You made me cry. I love you.”
Speaking to a reporter, Lady Gaga branded her fellow popstar an ‘inspiration’.
“The way she was treated in this business was really wrong,” Gaga began.
“And the way that women are treated in the music industry is something that I wish would change.
“I think that she will forever be an inspiration to women.”
Britney and Christina met almost 30 years ago in 1993 when they starred together on Disney Channel’s The Mickey Mouse Club. Ryan Gosling and Justin Timberlake also featured on the programme at the same time.
The pair launched their solo careers in 1998 and 1999, growing up together in the music industry.
Because of similarities between the pair, the media and the public pitted them against each other as rivals, something which caused tensions between the pair.
Throughout the following years, the pair took jibes at each other in interviews. However in the following years it seemed as though they patched things up with Christina posting praise for Britney online in 2018 'Well behaved women rarely make history', she captioned an Instagram post sharing a picture of Spears to mark International Women’s day.