The actor’s spouse, Joan Washington, died from lung cancer last September.
“My heart goes out to him for the incalculable loss of his beloved mother.”
The tweet was accompanied by photographs of the actor meeting with then-Prince Charles.

Richard E. Grant and the then-Prince Charles.Tim P. Whitby - Pool/Getty Images
The couple married in 1986.
Grant announced his wife’s passing on Sept. 3 of last year.
“Joan - Love of my Life & Giver of Life to our daughter Olivia.
Our hearts are broken with the loss of your Life last night,“the actor wrote on Twitter.
“35 years married & 38 together.
To be truly known and seen by you, is your immeasurable gift.
Do not forget us, sweet Monkee-mine.”
Grant writes extensively about his late wife’s illness in his upcoming book,A Pocketful of Happiness.
“But then I remembered some advice Bruce gave me about screenwriting.