British pop star Ed Sheeran feared his Australian tour would have to be scrapped after he began suffering vocal problems while on the road.

The Thinking Out Loud hitmaker struggled to sing during his recent trip Down Under, and he blames regular plane travel and air conditioning for damaging his voice.

Sheeran battled on with the tour, but he cut out partying and changed his setlist to make sure he could continue.

He tells the Sydney Daily Telegraph, "It was scary. It was a difficult tour in that respect, a lot of air conditioning and a lot of flying dries you up... I had to be more sensible than I usually am. (Hit song) One was in there (the setlist) but because my voice went I couldn't do falsetto. It had to come out... It'll be different when I come back to Australia in December."