WASHINGTON, United States (AFP) – Seven of the top hospitals in the United States lashed out at President Donald Trump’s refugee and travel ban on Wednesday, saying it would harm medicine and take the nation backward.

The lead author of the commentary article in the New England Journal of Medicine was Katrina Armstrong, physician in chief at Massachusetts General Hospital (MGH).

“Immigration policy that blocks the best from coming to train and work in the United States and blocks our trainees and faculty from safely traveling to other countries is a step backward, one that will harm our patients, colleagues, and America’s position as a world leader in health care and innovation,” it said.

“The consequences of this approach for US health care, and our field of internal medicine, are far reaching and damaging.”

The restrictions target people from seven Muslim-majority countries, temporarily banning nationals from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen for 90 days.

The letter was signed by doctors at Johns Hopkins University Hospital, University of Michigan Health System, Brigham and Women’s Hospital, University of Pennsylvania Perelman School of Medicine, University of California, San Francisco and Beth Israel Deaconess Medical Center.

The US doctors said the foreign-born physicians and scientists were vital to US hospitals and academic medical centers, as well as to US-based global health and disaster relief efforts.

“Over the past 50 years, the US biomedical research enterprise has benefited greatly from the ideas, creativity, ingenuity and drive of international medical graduates and other non-US nationals engaged in biomedical research,” said the article, describing those affected as “low-risk.”

Trump’s executive order, which was issued Friday, directly affected more than 100 personnel at Boston-based Partners HealthCare, which includes MGH and Brigham and Women’s Hospital, said the article.

About 24 per cent of doctors practicing in the United States are international medical graduates.