Former US First Lady Melania Trump has expressed her “deep sadness” at the death of her mother, Amalija Knavs, at the age of 78.

Trump announced the death on social media without disclosing the cause.

“It is with deep sadness that I announce the passing of my beloved mother, Amalija,” she wrote on social media platform X.

“Amalija Knavs was a strong woman who always carried herself with grace, warmth, and dignity.

“She was entirely devoted to her husband, daughters, grandson, and son-in-law.

“We will miss her beyond measure and continue to honour and love her legacy.”

Donald Trump also posted tribute to the “incredible” woman.

“This is a very sad night for the entire Trump family!!!” Trump wrote on his social media site, Truth Social.

“Melania’s great and beautiful mother, Amalija, has just gone to a beautiful place in the sky.

“She was an incredible woman, and will be missed far beyond words!”

He had previously revealed his mother-in-law’s poor health during a New Year’s Eve celebration at his Mar-a-Lago estate.

Trump had shared that Melania’s mother was “very ill” and his wife was with her at a hospital in Miami.

“It’s a tough one, very tough one,” he said of the situation.

Viktor and Amalija Knavs, the parents of former US First Lady Melania Trump, in 2017. Photo: Getty

During the Trump presidency, the first lady’s mother lived in New York along with her father, Viktor Knavs, and occasionally appeared at the White House.

Amalija Knavs was at a 2018 ceremony where the first lady debuted her “Be Best” public awareness campaign to help children.

Melania Trump sponsored her parents’ immigration to the US, and they took the oath of office to become citizens at a New York City courthouse in 2018, while Trump was president.

Melania Knauss and her mother Amalija Knavs at a Fashion Week event in New York in 2004. Photo: Getty

The Slovenian immigrants, a former car dealer and textile factory worker, had been living in the US as permanent residents.

Their lawyer said at the time that they applied for citizenship on their own and did not receive any special treatment.

The Knavses raised Melania, born Melanija, in the rural industrial town of Sevnica while Slovenia was under Communist rule.

She attended high school in the Slovenian capital, Ljubljana, and changed her name to Melania Knauss when she started modelling.

She settled in New York in 1996 and met Trump two years later.

They married in 2005.

Amalija Knavs (left), Donald and Melania Trump, Barron Trump, and Viktor Knavs on Christmas Day at Mar-a-Lago in 2008. Photo: Getty