Andris Nelsons will leave his post as music director of the City of Birmingham Symphony Orchestra when his contract comes to an end in 2015.
Nelsons was appointed the next music director of the Boston Symphony Orchestra earlier this year.
In a statement he said: 'With an extremely heavy heart I have reached this decision not to continue in my role as music director with my beloved CBSO. This difficult decision comes in view of my new position with the Boston Symphony Orchestra alongside my wish to protect precious time with my young family.'
Andris landed the contract in Birmingham in 2008, when he was a relatively unknown conductor, following on from music directors such as Louis Frémaux and Sir Simon Rattle.
Andris is to begin his contract with the Boston Symphony Orchestra as music director at the beginning of the 2014-2015 season. However, it is still expected that he will continue to take part in international projects, and to work with the City of Birmingham Symphony Orchestra as a guest conductor.