AceShowbiz - Ed Sheeran has blamed his toilet trouble at a recent concert on misjudging the amount of water he drank before going on stage.

The "Thinking Out Loud" singer performed in Cardiff, Wales on Saturday, June 23 - but had to leave the stage twice to relieve himself during the gig.

Ed has now explained why he was caught short.

"So I was there, I was playing, I was singing - but it was getting worse and worse and worse; you know when you start sweating?" he told British MC Big Narstie on his new U.K. TV chat show.

"The problem is, because I play the show solo, I can't just be like 'Hey band, start playing!' So I literally had to put the guitar down and be like, 'Talk among yourselves.' Usually, (with) the adrenaline and all the water you drink, you sweat out. But I drank so much water before the show."

Some fans expressed disappointment in the singer-songwriter for legging it off stage, as he halted his song "Photograph" to take one break. However, most were sympathetic to his bladder emergency, and Ed told Narstie and co-host Mo Gilligan that dashing to the toilet was better than the alternative.

"You know when you gotta go, you gotta go," he said. "I thought interrupting a show to be like, 'I'm going off stage' is far better than a picture in the paper the next day."

Although the 27-year-old has never halted a gig to go to the loo before, in 2015 he told Australia's Nova FM radio he had accidentally soiled his pants on stage - but carried on performing.

Big Narstie's interview with Ed's will air on U.K. network Channel 4 on Friday.