Travis Kelce has set 'golden rule' for marrying Taylor Swift and it could delay 'wedding of the century'

Travis Kelce has set a 'golden rule' for marrying Taylor Swift and it could delay their wedding.

Kelce and Swift started dating last year and went public with their relationship when she appeared at one of the NFL star's games at Kansas City's Arrowhead Stadium.

She took a seat alongside the American football player's mum, Donna, for the fixture last September.

Their romance has since blossomed, with the couple often pictured together.

Swift was in attendance for 13 NFL matches last season, including the Super Bowl. As for 35-year-old tight-end, he travelled to several of her tour dates across the globe during the offseason.

And they are ready to take the next step, but Kelce will not pop the question until one condition is met.

According to a source quoted by Life and Style, Kelce won't propose to Swift until the couple have agreed a prenup.

They want financial terms in place for if they were to ever split up.

Travis Kelce and Taylor Swift seen out in New York City. Image: Getty

The source is quoted as saying: "This is a lot further along than either Taylor or Travis would care to admit, since they’ve considered themselves unofficially engaged for a while and are both 100 percent committed to spending the rest of their lives together and starting a family.

"The formalities are just their schedules that have gotten in the way, as well as the logistics of a prenup, which is obviously complicated by the vast amounts of money involved on both sides.

"There’s just no way Taylor would walk down the aisle without a prenup.

"They both want it figured out before Travis gets down on one knee."

Swift, 34, is a billionaire thanks to her thriving music career while Kelce, who's a three-time Super Bowl winner with the Chiefs, has an estimated worth of around $70 million.

If they do indeed tie the knot, then it's expected to be the 'wedding of the century'.