The singer for Maneskin, Italy's Eurovision Song Contest winning rockers, is to take a "voluntary drug test" after denying speculation that he was snorting cocaine during the broadcast, organizers said Sunday.

Red lederhosen-clad vocalist Damiano David will be tested after going back to Italy, following viral footage of him leaning over a table in the hospitality area of the competition in Rotterdam.

"We are aware of the speculation surrounding the video clip of the Italian winners of the Eurovision Song Contest in the Green Room last night," the European Broadcasting Union (EBU) said in a statement.

"The band have strongly refuted the allegations of drug use and the singer in question will take a voluntary drug test after arriving home," it added.

"This was requested by them last night but could not be immediately organized by the EBU."

The Maneskin singer was asked about the footage during the winners' press conference early on Sunday, and said he had been looking down because guitarist Thomas Raggi had broken a glass.

"I don't use drugs. Please, guys. Don't say that really, no cocaine. Please, don't say that," David said.

The band later said on their Instagram stories that they were "ready to get tested because we have nothing to hide."

"We are really shocked about what some people are saying about Damiano doing drugs. We really are AGAINST drugs and we never used cocaine," they said.

The EBU said evidence at the scene backed up David's account about the glass smashing.

"The band, their management and head of delegation have informed us that no drugs were present in the Green Room and explained that a glass was broken at their table and it was being cleared by the singer," its statement said.

"The EBU can confirm broken glass was found after an on-site check. We are still looking at footage carefully and will update with further information in due course."

Maneskin fought off stiff competition from France and Switzerland, surging to victory on the back of the public vote to win with 524 points.