FILE PHOTO: U.S. President Donald Trump speaks during a cabinet meeting at the White House in Washington, U.S., July 31, 2017. REUTERS/Joshua Roberts/File Photo - RC1820BA0970

UNITED NATIONS (Reuters) - A United Nations rights expert voiced concern on Wednesday that Trump administration actions would be harmful to a free press in the United States.

“There’s a long-term detrimental impact on respect for ... First Amendment values, which are also human rights,” said David Kaye, the U.N. Special Rapporteur on freedom of opinion and expression.

The First Amendment to the U.S. Constitution guarantees freedom of speech and of the press.

U.S. President Donald Trump has called the press the enemy of the American people. He uses the term “fake news” to cast doubt on news reports critical of his administration, often without providing evidence to support his case.

Speaking to journalists at the United Nations, Kaye accused the administration of limiting access to information about the environment and climate change. Trump has called global warming a hoax.

Kaye called for greater media access to Secretary of State Rex Tillerson and voiced concern about the pressure on journalists he said had emerged from “the very clear agenda” of Attorney General Jeff Sessions.

The White House did not immediately respond to a request for comment, nor did the Justice or State departments.

Sessions said in August the Trump administration was weighing requiring journalists to reveal their sources amid Trump’s push to stop leaks to the press from people in government.