PA Sport understands Mamadou Sakho won't challenge his failed drugs test PA Sport understands Mamadou Sakho won't challenge his failed drugs test

Mamadou Sakho will not contest the result of his positive drug test, according to the Press Association.

The Liverpool defender is understood to have returned a positive test for a fat-burning substance after last month's Europa League game at Manchester United.

Sakho had until a UEFA deadline on Tuesday to request testing on a 'B' sample, but he did not take up the option and has instead accepted the initial result.

Jurgen Klopp says Liverpool can only wait and find out what punishment Mamadou Sakho will face Jurgen Klopp says Liverpool can only wait and find out what punishment Mamadou Sakho will face

The France international is not currently suspended but was left out of Liverpool's squad for Saturday's draw with Newcastle and has not travelled to Spain for Thursday's Villarreal game.

Speaking on Wednesday evening in Spain, Jurgen Klopp, when asked about Sakho's situation, said: "Really nothing else to say. What they're all doing is collecting info to clear situation up. Have to wait for next steps."

Former Reds defender Jamie Carragher last weekend told Sky Sports Sakho had "let himself and the club down very badly."

"There are serious questions to be asked of him," Carragher said. "It's a nightmare for the player because he was becoming really important for Liverpool."

Sakho's Liverpool team-mate Kolo Toure tested positive for a banned substance during his time at Manchester City and was banned for six months under Football Association rules.