March 6 (Reuters) - Former United States trade representative Robert Lighthizer resigned from Trump Media & Technology Group's DJT.O board of directors, effective Friday, an SEC filing showed.

During U.S. President Donald Trump's first term, Lighthizer played a crucial role as trade chief in the imposition of hefty tariffs on Chinese imports and the renegotiation of the North American Free Trade Agreement, or NAFTA, with Mexico and Canada.

His departure from the board and its committees was not due to any disagreements with the company's management or the board, the filing said.

Founded by Trump and known for its Truth Social platform aimed at conservative audiences, TMTG has struggled to scale its media business amid competition from larger social networks and uneven user growth.

TMTG has been considering spinning off Truth Social into a publicly traded company.

In a strategic pivot in December, the company agreed to merge with California-based TAE Technologies in an all-stock deal valued at over $6 billion, shifting its focus to fusion energy and forming a publicly traded company developing utility-scale power plants to meet rising electricity demand, including from AI data centers.

(Reporting by Anhata Rooprai in Bengaluru; Editing by Alan Barona)

((Anhata.Rooprai@thomsonreuters.com))