Prince William and Kate release previously-unseen wedding photo

As Kate remains out of the spotlight amid her cancer battle, the couple has celebrated their wedding anniversary with a sweet tribute.

Prince William and Princess Catherine have released a previously unseen portrait of themselves to mark their anniversary. Picture: Supplied

The Prince and Princess of Wales have shared a previously-unseen portrait from their wedding day in honour of their 13th anniversary.

A beaming William is seen with his arms wrapped around his bride in the black-and-white picture, taken on April 29, 2011, by photographer Millie Pilkington, and released on Monday via Kensington Palace.

For the big day, Kate was famously dressed in a custom Sarah Burton gown, accessorised with her Cartier “Halo Tiara”, while William donned the scarlet tunic of the Irish Guards.

The couple has released a previously-unseen portrait of themselves to mark their anniversary. Picture: Supplied

The stunning new portrait comes amid Kate’s ongoing break from royal duties as she undergoes treatment for cancer.

During an emotional video released in March where she revealed her diagnosis, Kate praised her husband of more than a decade for his support during “an incredibly tough couple of months for our entire family”.

“Having William by my side is a great source of comfort and reassurance,” she said.

After the video was released, William also took a break from the spotlight as he spent time with his wife and their three children – Prince George, 10, Princess Charlotte, eight, and Prince Louis, who turned six last week.

William returned to work earlier this month. Picture: David Rose/Pool/AFP

The couple’s 2011 wedding was watched by millions. Picture: Chris Jackson/Getty Images

However, he returned to work earlier this month, where he promised wellwishers that he would continue to “look after” Kate.

The couple, who first met while studying at St Andrew’s University near Dundee in Scotland, announced their engagement in 2010 following a holiday proposal.

“We had a little private time away together with some friends, and I just decided it was the right time, really,” William said in an interview shortly afterwards.

“We’d been talking about marriage for a while, so it wasn’t a massively big surprise, but I took her up somewhere nice in Kenya.”

The couple’s 2011 televised wedding ceremony, held at Westminster Abbey in London, was watched by more than 160 million people all over the world.