Two decades after claiming to have had a four-month affair with David Beckham, his former assistant Rebecca Loos is opening up once again, reaffirming her accusations and reflecting on the personal toll the saga took on her.

Speaking candidly in a new interview with 60 Minutes Australia, Loos, now 47, stood by her story, insisting she "stuck to the truth" throughout the years.

Loos was thrust into the public eye in 2004 when, shortly after her time working for Beckham in Madrid, she alleged the two had an affair.

At the time, Beckham was married to his wife, Victoria Beckham, with whom he had two children.