Chris Coleman is set to become the new manager of Sunderland after resigning his position with Wales.
Sunderland are expected to confirm Coleman's appointment within the next 48 hours.
Coleman, 47, became the most successful manager in Welsh history when he guided the national team to the semi-finals of Euro 2016 in France.
Foottball Association of Wales chief executive Jonathan Ford said: "We are extremely disappointed to see Chris' tenure as Wales manager come to an end.
"The FAW and Wales as a nation will be eternally grateful for the job he has done over the last six years as national team manager, from travelling the length and breadth of Wales outside of the media spotlight to talk to players and supporters, to guiding us to the semi-finals of the European Championships.
"We wish Chris the very best of luck for the future as he returns to club management, a desire for which he has always been honest and open about."
Wales assistant manager Kit Symons has also resigned and is expected to join Coleman at the Stadium of Light.
Robbie Stockdale will be in charge for Sunderland's clash with Millwall on Saturday, but Coleman should be in the dugout for Tuesday's trip to Aston Villa.
Sunderland are currently bottom of the Sky Bet Championship and sacked Simon Grayson on October 31.
Northern Ireland manager Michael O'Neill and Barnsley's Paul Heckingbottom had both been heavily linked with the post.
But Coleman's appointment will be seen as something of a coup for Sunderland chief executive Martin Bain.
Coleman missed out on World Cup qualification last month, but his credit remains high after taking Wales to their first major tournament for 58 years.
He became the youngest manager in the Premier League when he was appointed Fulham manager at the age of 33 in 2003.
He took them to ninth but lost his job in 2007 and spent six months at Real Sociedad.
He then had unsuccessful spells with Coventry and Greek side AEL before Wales called.
Coleman took over Wales during the darkest point in their history following the death of his great friend Gary Speed.
He was appointed in January 2012 and struggled at first in a dismal 2014 World Cup qualifying campaign, which included an embarrassing 6-1 defeat in Serbia.
But Coleman recovered from those early difficulties to leave an indelible mark on Welsh football.
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