Donald Trump
Donald Trump makes an announcement in the Oval Office. REUTERS/Jonathan Ernst

The doctor who formerly treated Dick Cheney, longtime cardiologist Dr. Jonathan Reiner, called on Congress to launch an investigation into President Donald Trump's mental health over his obsession with owning Greenland.

In a recent letter, Trump linked his quest for Greenland to a failure to secure the Nobel Peace Prize.

"Considering your Country decided not to give me the Nobel Peace Prize for having stopped 8 Wars PLUS, I no longer feel an obligation to think purely of Peace, although it will always be predominant, but can now think about what is good and proper for the United States of America," Trump wrote to Norwegian Prime Minister Jonas Gahr Støre.

"I have done more for NATO than any other person since its founding, and now, NATO should do something for the United States. The World is not secure unless we have Complete and Total Control of Greenland," the U.S. president added.

Reiner suggested the letter was a cry for help.

"This letter, and the fact that the president directed that it be distributed to other European countries, should trigger a bipartisan congressional inquiry into presidential fitness," the doctor wrote on X.