WASHINGTON — Donald Trump fired off an indignant letter to Mayor de Blasio on Thursday claiming the mayor should say “thank you” instead of thinking about severing the city’s business dealings with the real-estate mogul.

“I would hope that the mayor and other political leaders would give me a thank-you for the great job we have done, instead of a reprimand,” Trump wrote.

De Blasio said last week that he would review city contracts with the billionaire whose comments about Mexican “rapists” caused a split with businesses.

Trump has developed several projects for the city, including the Wollman Rink in Central Park and the Trump Golf Links Ferry Point in The Bronx.