'Eurovision Song Contest' winner Salvador Sobral said he uses cocaine to keep up his energy on tour.

Salvador Sobral

Salvador Sobral

The 28-year-old Portuguese singer won the annual competition last year, and he has now claimed he turns to the class-A drug in an effort to keep himself going on the road.

Appearing on Spanish TV show 'El Hormiguero' this week, he was asked for his secret, and responded: "Well cocaine helps a lot. Oh, I am sorry I forgot they told me this may be a family show."

Sobral's interview also caused waves after he took the opportunity to criticise 'Eurovision' just over a year after his triumph, and suggested it is not about musical quality.

He added: "I think its an entertainment visual show -music is not very important, it's just a retail in the show.

"The song that won this year ['Toy' by Israeli singer Netta] is irrelevant to me. It doesn't touch you - it just doesn't say anything."

However, he previously heaped praise on his own winning song - 'Amar Pelos Dois' ('Love for Both of Us') - which was penned by his sister Luisa.

He previously described the ballad as "an emotional song with a beautiful lyrical message and harmony - things people are not used to listening these days".

His comments come after the star - who has suffered from a longstanding heart condition - underwent a heart transplant in December last year.

Speaking at the time, surgeon Miguel Abecasis, quoted by the Publico daily, said: "The surgery went well.

"He was very well prepared. He is a young man who understood the difficulties of this type of procedure."