Thomson Reuters Allergan CEO Brenton Saunders.
His company scrapped its $160 billion merger with Pfize on Wednesday, following the announcement of new rules Treasury that look to have been designed almost specifically to stop Pfizer from benefitting from the merger.
"This administration and these types of policies hurt America's ability to compete on a global scale," CEO Brent Saunders said in an interview with CNBC.
He added that the US was effectively building a wall around itself, and that these kinds of measures undermined confidence in the rule of law in the US.
"We built this deal along the regulations - all the notices that were put out by the Treasury - and it was a highly legal construct," he said.
"We followed the rules that Congress had set [and] for the rules to have changed after the game had started to be played is a bit un-American, but that's the situation we're in."
Asked whether he believed the Treasury had specifically targeted his deal, Saunders said, "It certainly appears that way."
He said that his company is a job creator, and that the idea that they shift jobs overseas was "preposterous."
"This idea that we take and don't give is simply not true," he said.
Saunders pointed out that Allergan, which is domiciled in Ireland, invests in the United States in the form of manufacturing, scientists, and research and development investments.
"Being inverted … allows us to more easily invest in the US than a US company," he said.
He added that his company pays taxes in the United States as well.
"With global companies like us, we look at the world - we look for certainty and rule of law... Do we need to start worrying about that in the greatest country in the world, the United States?" he said.
"I personally am an American, and am a patriot," he added.