UEFA confirms Sakho's failed drug test

And while France international Sakho is not formally suspended at this stage, he will not be considered for first-team duty until the matter is resolved - a decision taken by the club in conjunction with the player - with Liverpool likely to request the testing of a B sample.

Liverpool defender Mamadou Sakho has until Tuesday to request the B sample is examined.

UEFA has confirmed Liverpool defender Mamadou Sakho failed a drugs test following the Europa League game at Manchester United last month.

And while France international Sakho is not formally suspended at this stage, he will not be considered for first-team duty until the matter is resolved - a decision taken by the club in conjunction with the player - with Liverpool likely to request the testing of a B sample.

The 26-year-old tested positive for a banned substance after the 1-1 draw at Old Trafford on March 17 and could face a lengthy ban, with his participation at  Euro 2016 also now in doubt.

A Liverpool statement read: "Yesterday, Friday 22nd April 2016, a formal communication was received from UEFA stating that they are investigating a possible anti-doping rule violation by Mamadou Sakho.

"The player will respond to UEFA on the matter.

"The player is currently not subject to any playing suspension. However, the club, in consultation with the player, has decided that while this process is followed the player will not be available for selection for matches.

"There will be no further comment at this time."

Sakho has until Tuesday to request the B sample is examined.

A UEFA statement read: "UEFA would like to confirm the information communicated by Liverpool FC regarding an adverse finding in a doping test of their player Mamadou Sakho conducted at the UEFA Europa League match between Manchester United FC and Liverpool FC on 17 March 2016 (1-1).

"The player and the club have received all the pertinent information and have until Tuesday to request the analysis of the B sample as well as to provide explanations for the presence of a prohibited substance in the players' body. 

"There are no disciplinary proceedings opened at this stage." 

Sakho's Liverpool team-mate Kolo Toure was banned for six months in 2011 after taking slimming tablets belonging to his wife.

Sakho, who joined Liverpool in August 2013 from Paris Saint-Germain, has been a regular for the club this season, making 22 Premier League appearances and scoring in its 4-0 derby win over Everton in midweek.

He also grabbed a vital goal as Liverpool completed a remarkable comeback to beat Borussia Dortmund 4-3 in the Europa League quarterfinals on April 14.