Stefano Gabbana and Domenico Dolce have branded calls from the likes of Sir Elton John and Ricky Martin to boycott their clothing line ''medieval''.

The design duo have hit out after stars including Sir Elton John, Courtney Love and Ricky Martin took a stance against the brand following comments they made in a recent interview, in which they discussed their opposition to gay adoption and branded children conceived via fertility treatment ''synthetic''.

Gabbana said: ''Boycott Dolce & Gabbana for what? They don't think like you? This is correct? This is not correct. We are in 2015. This is like medieval. It's not correct.''

His design partner - and former lover - said his stance is based on his own Sicilian upbringing but insisted he ''respects'' other people's views. He said: ''I believe in the traditional family. It is impossible to change my culture for something different. It's me... I respect all the world, all the culture.''

And it seems Gabbana may have a different opinion to Dolce , as he insisted he supports both IVF and gay adoption. In a joint interview with CNN, asked whether he supported having children through IVF, Gabbana said: ''Yeah, I don't have anything bad, because the beauty of the world is freedom... ''We love gay couple. We are gay. We love gay couple. We love gay adoption. We love everything. It's just an express of my private point of view.''

The row was sparked by an interview conducted by Italian publication Panorama, in which Dolce was quoted as saying: ''Wombs for rent, sperm selected from a catalog... Who would agree to be the daughter of chemistry? Procreation must be an act of love, now not even psychiatrists are prepared to deal with the effects of these experiments.''

Following the comments, 'Rocket Man' hitmaker Elton - who has sons Zachary, four, and Elijah, two, with husband David Furnish - lead the calls for a boycott of the designers.

He wrote on Instagram: ''How dare you refer to my beautiful children as 'synthetic'. And shame on you for wagging your judgemental little fingers at IVF - a miracle that has allowed legions of loving people, both straight and gay, to fulfil their dream of having children. Your archaic thinking is out of step with the times, just like your fashions. I shall never wear Dolce and Gabbana ever again. #BoycottDolceGabbana''