Blake Lively, the American actress, has apologised for making a “photoshop” jibe about the Princess of Wales weeks before she announced she has cancer.

Lively, 36, who starred in the US drama series Gossip Girl, made a joke alluding to the Princess’s absence from public life when launching her drinks range earlier this month. She wrote: “I’m so excited to share this new photo I just took today to announce our 4 new @bettybuzz & @bettybooze products! Now you know why I’ve been MIA.”

After the Princess’ announcement on Friday, Lively wrote on Instagram: “I’m sure no-one cares today but I feel I have to acknowledge this.

“I made a silly post around the ‘photoshop fails’ frenzy and, oh, man, that post has me mortified today.”

The Princess of Wales’s revelation that she is undergoing treatment for cancer has sparked an outpouring of support and well wishes from around the world.

In an emotional video message, Kate spoke about the “huge shock” after tests identified cancer following her abdominal surgery and the “incredibly tough couple of months” her family have experienced.

Follow the latest updates below.