Elton John "will love David Furnish forever".

Elton John and David Furnish

Elton John and David Furnish

The 'Rocket Man' singer tied the knot with his partner at their estate in Windsor in south east England last December, on the ninth anniversary of their civil partnership, and on Sunday (25.10.15) Elton posted a gushing birthday message to David on his Instagram account.

Elton, who has sons Zachary and Elijah, with David, wrote: "Happy Birthday to my beautiful, wonderful man. I will love you forever @davidfurnish. #ShareTheLove #HappyBirthday (sic)."

The couple - who met in 1993 - have championed for same-sex couples to be allowed to marry in the UK for many years, with legislation allowing it coming into force in March 2014.

The decision to wed came nine years after they committed themselves to each other in a lavish ceremony at the Windsor Guildhall which was attended by Victoria Beckham and Helena Bonham Carter among other stars.

Last year's ceremony took place next to a Damien Hirst altar, and featured their two sons as the ring bearers, with the gold bands attached to cuddly rabbit toys which they carried up the aisle.

Following the nuptials, guests enjoyed a lavish three-course meal of wild mushroom soup, beef and onion pie and warm chocolate pudding, before the newlyweds cut a personalised wedding cake for their friends to enjoy.