She posted about it on her Facebook page.

"Our hearts are heavy. This afternoon - Claude, my husband of so many amazing years - passed away - leaving us lost for words to describe this awful emotion - grief.
Thank you my lovely children, and friends, for giving me strength to get through this overwhelming sadness.
Peace be with you chéri.❤️
R.I.P. Claude Wolff (1931-2024)"

Thoughts and Prayers go out to Petula herself