Cheryl has sparked engagement rumours after sporting a ring with what appears to be a diamond in it at a royal reception.

The former Girls Aloud star joined Dame Helen Mirren and Sir Tom Jones to meet the Prince of Wales at St James’s Palace in London for an Invest In Futures gala for The Prince’s Trust.

However, it was the piece of jewellery on the third finger of the 34-year-old’s left hand that stole the show.

Cheryl Cheryl at The Prince’s Trust event (John Phillips/PA)

The singer and TV personality, who is in a relationship with One Direction star Liam Payne, was pictured wearing the ring as she greeted Charles.

She has not commented on whether it is an engagement ring from Payne.

The couple, who have not been seen together on their social media accounts for several months, welcomed their son, Bear, in March last year after being an item since 2016.

They first met on The X Factor in 2008 when Cheryl was a judge and Payne auditioned as a solo contestant, two years before becoming part of the hit boyband One Direction on the programme.

Date night 😏

A post shared by Cheryl (@cherylofficial) on Jul 6, 2017 at 2:36pm PDT

Cheryl has been married twice before – first to footballer Ashley Cole, and then French restaurateur Jean-Bernard Fernandez-Versini.

Cheryl and the other stars attended the event to mark one year of partnership between The Prince’s Trust and beauty brand L’Oreal.