A New York City medical school will offer students free tuition following a $1bn donation from the 93-year-old widow of a major Wall Street investor.

The gift to Albert Einstein College of Medicine came from Dr Ruth Gottesman, a former professor at the Bronx school.

It is one of the largest ever donations made to a US school and is the largest ever made to a medical school.

The Bronx, New York City's poorest borough, is ranked as the unhealthiest of New York's 62 counties.

In a statement, university dean Dr Yaron Yomer said that the "transformational" gift "radically revolutionises our ability to continue attracting students who are committed to our mission, not just those who can afford it".

Tuition at the school is nearly $59,000 each year, leaving students with substantial debt.

The statement from Einstein noted students in their final year will be reimbursed for their spring 2024 tuition, and from August, all students, including those who are currently enrolled, will receive free tuition.

The donation "will free up and lift our students, enabling them to pursue projects and ideas that might otherwise be prohibitive", Dr Yomer added.

Dr Gottesman, now 93, began working at the school in 1968. She studied learning disabilities, ran literacy programmes and developed widely used screening and evaluation protocols.

Her late husband, David Gottesman, founded a prominent investment house and was an early investor in Berkshire Hathaway, Warren Buffet's multinational conglomerate. He died in September 2022 at the age of 96.

Dr Gottesman said in a statement that the doctors who train at Einstein go on to "provide the finest healthcare to communities here in the Bronx and all over the world".

"I am very thankful to my late husband, Sandy, for leaving these funds in my care, and l feel blessed to be given the great privilege of making this gift to such a worthy cause," she added.

About 50% of Einstein's first-year students are from New York, and approximately 60% are women. Statistics published by the school show that about 48% of its medical students are white, while 29% are Asian, 11% are Hispanic and 5% are black.

In an interview with the New York Times, she recalled that her late husband had left her a "whole portfolio of Berkshire Hathaway stock" when he died with the instructions to "do whatever you think is right with it".

"I wanted to fund students at Einstein so that they would receive free tuition," Dr Gottesman said she immediately realised. "There was enough money to do that in perpetuity."

She added that she occasionally wonders what her husband would have thought of the donation.

"I hope he's smiling and not frowning," she said. "He gave me the opportunity to do this, and I think he would be happy - I hope so."