Jamie Lee Curtis and Kristen Bell honour You Again co-star Betty White

Jamie Lee Curtis and Kristen Bell have paid tribute to their You Again co-star Betty White.

The Hollywood legend died of natural causes at the age of 99 on 31 December, with many celebrities honouring her over the weekend.

Among those was Curtis, who remembered White with a sweet message shared via Instagram on Saturday.

"One last fond farewell. A life of grace and laughter and LOVE! We were so lucky to be able to be in her orbit!" she wrote alongside a snap of the You Again cast at a premiere in 2010.

She also posted a copy of a cover photoshoot she did with Bell and White for AARP magazine and urged fans of the TV icon to donate to animal advocacy groups in her memory.

"What women WANT is to live a life like Betty White. Full of love and creativity and integrity and humor and dedication and a life of service to animals. To honor her today please make a donation to the @morrisanimalfoundation Morris Animal Foundation or any animal advocacy group! She would LOVE that. Rest easy you beautiful woman. We will carry on for you!" she insisted.

Bell reposted Curtis's message and added: "Betty was one of a kind. Kind, gracious and wit that could stun a sailor. Thank you, Betty, for showing so many of us how to live."

You Again, also starring Sigourney Weaver and Odette Annable, marked White's final onscreen role.

Elsewhere, U.S. President Joe Biden paid tribute to White in a statement in which he described her as a "lovely lady" and "cultural icon who will be sorely missed", while Ryan Reynolds, Sandra Bullock, Ellen DeGeneres, Paul Feig, Andy Cohen, and Kathy Griffin also shared messages about the star.