March 11 (Reuters) - U.S. President Donald Trump on Tuesday said he will buy a new Tesla car to show support for the electric carmaker's chief and his ally Elon Musk amid recent "Tesla Takedown" protests and the slump in the company's stock price.

Musk's role in sweeping cuts to the federal workforce at the behest of Trump has led to protests in the U.S. against Tesla.

About 350 demonstrators protested outside a Tesla electric vehicle dealership in Portland, Oregon, last week, while nine people were arrested during a raucous demonstration outside a New York City Tesla TSLA.O dealership earlier in March.

Musk is spearheading the Trump administration's so-called Department of Government Efficiency, or DOGE.

In a post on his Truth Social platform, Trump defended Musk by saying he was "putting it on the line” to help the country and was doing a "fantastic" job.

"I'm going to buy a brand new Tesla tomorrow morning as a show of confidence and support for Elon Musk, a truly great American," Trump said.

Musk thanked the president for his support on his own social media platform X.

Tesla's market capitalization has more than halved since hitting an all-time high of $1.5 trillion on December 17, erasing most of the gains the stock made after Musk helped finance the election victory of U.S. President Donald Trump.

The stock's decline since December stems from falling vehicle sales and profits, protests of Musk's political activity and investor worries that politics are distracting the world’s richest man from tending to his cash cow.

(Reporting by Shubham Kalia in Bengaluru; Editing by Michael Perry)

((Shubham.Kalia@thomsonreuters.com;))