Barbara Bush, the wife of former US president George HW Bush and mother of President George W Bush, has died aged 92.

On Sunday it was announced the former first lady was in “failing health” and had decided to no longer seek medical treatment.

Her son George W Bush, the 43rd US president, thanked everyone for their prayers and good wishes in a statement confirming her passing.

“Barbara Bush was a fabulous First Lady and a woman unlike any other who brought levity, love and literacy to millions,” he said.

“To us, she was so much more. Mom kept us on our toes and kept us laughing until the end.

“I’m a lucky man that Barbara Bush was my mother. Our family will miss her dearly, and we thank you for your prayers and good wishes.

“Laura, Barbara, Jenna and I are sad, but our souls are settled because we know hers was. ”

Statement by the Office of @GeorgeHWBush on the passing of Barbara Pierce Bush this evening at the age of 92. pic.twitter.com/c6JU0xy6Vc

— Jim McGrath (@jgm41) April 17, 2018

Mrs Bush had endured a series of recent hospitalisations and the office of her husband had said she would “focus on comfort care”.

CNN reported that Mrs Bush was suffering from chronic obstructive pulmonary disease and congestive heart failure. A Bush family spokesman said she was being cared for at her home.

As first lady from 1989 until the start of 1993, Mrs Bush was a popular national figure known for her sometimes blunt talk and self-deprecating wit. Her husband, the 41st US president, is 93 years old.

Another son, Jeb, is a former governor of Florida who ran unsuccessfully for president in 2015 and early 2016, quitting after a series of lacklustre performances highlighted by tough skirmishes with then-candidate Donald Trump.

With hair that had turned white prematurely, Mrs Bush was known by family members as the “Silver Fox”.

Barbara Bush with her husband George HW Bush. Photo: AAP

Her work as first lady focused on promoting literacy and reading. At the time, she said she was more interested in running a household than in helping her husband run the country.Po

Mrs Bush holds a unique place in US history.

She is the only woman to see her husband and son sworn in as US president. Abigail Adams, first lady from 1797 to 1801, was a major influence on husband John Adams, the nation’s second president, but died before her son, John Quincy Adams, was elected president in 1824.

Political leaders and celebrities around the world blessed Mrs Bush’s memory in tweets on Wednesday morning (AEST). Former president Bill Clinton said “Barbara Bush was a remarkable woman. She had grit & grace, brains & beauty”.

Barbara Bush was a remarkable woman. She had grit & grace, brains & beauty. She was fierce & feisty in support of her family & friends, her country & her causes. She showed us what an honest, vibrant, full life looks like. Hillary and I mourn her passing and bless her memory.

— Bill Clinton (@BillClinton) April 17, 2018

Always a friend to Canada, Barbara Bush leaves a legacy of dignity, grace, service and devotion to family. Sophie and I send our deepest condolences to Presidents George H.W. and George W. Bush, their family, and to all Americans.

— Justin Trudeau (@JustinTrudeau) April 18, 2018

Throughout her life, Barbara Bush showed us all the importance of charity, literacy, and love of country. Our thoughts are with the entire Bush family as they mourn her passing. Rest In Peace.

— Tim Cook (@tim_cook) April 18, 2018

President Donald Trump released a statement on Twitter, offering his thoughts and prayers to the Bush family.

“Mrs Bush was an advocate of the American family. Amongst her greatest achievements was recognising the importance of literacy as a fundamental family value that requires nurturing and protection,” he said.

“She will be long remembered for her strong devotion to country and family, both of which she served unfailingly well.

“The President and First Lady’s thoughts and prayers are with the family and friends of Mrs Bush.”