Gap - Russian Alexandr Kolobnev's B sample also tested positive for a banned diuretic, his Katusha team said on Wednesday.
Kolobnev left the Tour de France last week after testing positive for hydroclorotiazide following the fourth stage of the race.
"Since Alexandr Kolobnev's B sample came back positive, Team Katusha confirms the suspension of the rider," Katusha said in a statement.
"Kolobnev, formally, suspended himself," the statement added.
A decision on whether Kolobnev will be fired will be made after the Russian federation reviews the case, the team said.
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