Billy Joe Saunders said he is "a clean fighter to the bone" after it was confirmed he has not breached anti-doping regulations.

Reports emerged that the WBO middleweight champion returned an adverse analytical finding in a test carried out by the Voluntary Anti-Doping Association.

Promoter Frank Warren revealed the 29-year-old Briton had used a nasal spray and was not in breach of British Boxing Board of Control and United Kingdom Anti-Doping rules.

Saunders is due to defend his strap against Demetrius Andrade in Boston on October 20.

"I'm a clean fighter to the bone and always have been and I'm ready to go on the 20th," Saunders tweeted.

Warren said in a statement: "Following reports of an adverse analytical finding in a test carried out by the Voluntary Anti-Doping Association (VADA) on WBO world middleweight champion, Billy Joe Saunders, we can confirm that the product concerned is permitted to be used 'out of competition' by United Kingdom Anti-Doping (UKAD) in line with the regulations of the World Anti-Doping Agency (WADA).

"For the avoidance of doubt, the product in question was a common decongestant nasal spray.

"The British Boxing Board of Control (BBBofC) under whose jurisdiction Billy Joe Saunders is licensed are affiliated only to UKAD/WADA.

"The BBBofC have confirmed that Mr Saunders is not in breach of BBBofC or UKAD anti-doping regulations and is therefore in good standing and is licensed to box and defend his world title on October 20th.

"Mr Saunders has been tested a number of times in 2018, all negative, his last out of competition test by UKAD was on 24th September 2018."