LOS ANGELES -- US President Donald Trump said on Sunday that he is authorizing to immediately begin the process of instituting a 100 percent tariff on all movies "produced in Foreign Lands."

In a post on his Truth Social platform, Trump wrote, "The Movie Industry in America is DYING a very fast death."

"Other Countries are offering all sorts of incentives to draw our filmmakers and studios away from the United States. Hollywood, and many other areas within the USA., are being devastated," Trump said in the post, calling the situation "a National Security threat."

"Therefore, I am authorizing the Department of Commerce, and the United States Trade Representative, to immediately begin the process of instituting a 100 percent Tariff on any and all Movies coming into our Country that are produced in Foreign Lands. WE WANT MOVIES MADE IN AMERICA, AGAIN!" he added.

Trump's announcement caused a stir nationwide, especially in the film industry. The Hollywood Reporter, a major Hollywood industry magazine, wrote that it "could shake up the entertainment industry."

"There are a number of expensive tentpoles due out in the coming months that filmed overseas. Would they be grandfathered in via a grace period or hit with a tariff?" the news outlet asked.

Variety, another major industry news outlet, also said that it's "a move that sent shockwaves through Hollywood."

"Studio executives convened emergency calls after Trump issued his declaration, though there is enormous uncertainty about whether the president has the authority to institute these tariffs, as well as how they would work practically," Variety reported. "It was also unclear what the impact would be on the many films that shoot overseas."

"Trump has complained about trade deficits as he has imposed tariffs on other countries, but the movie industry has been a bright spot," said Deadline, a premier publication for Hollywood business, adding that the industry generated a positive balance of trade in every major market in the world, with exports 3.1 times that of imports.

"Other countries also could respond to the 100 percent tariff with their own duties on US films, which would have an impact on international box office returns, which are a huge chunk of major studio revenue," the news outlet warned.