TNT Post UK sales and marketing director Marc Caulfield has left the company to pursue other opportunities.
Caulfield joined the company in 2010, having previously run his own consultancy.
He has also worked a number of advertising and media agencies including in head of direct roles at MPG and Initiative.
TNT has not appointed a successor and is reviewing the post.
In a statement, TNT said Caulfield left "on amicable terms" and it was "appreciative of all the work he has done over the past year".
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