Saidy Janko has left Celtic to sign a four-year contract with St Etienne in France.
The 21-year-old full-back joined the Scottish champions from Manchester United in the summer of 2015.
The Switzerland Under-21 international made seven appearances for Celtic last season before being loaned out to Barnsley.
"Joining a club of this magnitude is a great opportunity for me," Janko told the Ligue 1 club's website.
"This is one of the biggest French clubs with a wonderful history and fantastic supporters. Yesterday I visited the Geoffroy-Guichard Stadium. It is a very impressive stadium that resembles Celtic Park.
"Physically, I feel very good. I resumed training with Celtic two weeks ago."
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