WASHINGTON (REUTERS, AFP) - Mrs Barbara Bush, the wife of former US President George H.W. Bush, is in "failing health"and has decided to no longer seek medical treatment, the office of the ex-president said in a statement from Houston on Sunday (April 15).

The former first lady, the statement said, "will instead focus on comfort care."

She is 92 years old. Her husband, the 41st US president, is 93 years old.

The statement provided no details on her condition, but Mrs Bush had been hospitalized for bronchitis treatment in January 2017.

She had heart surgery in 2009, and was operated on for an ulcer the year before. She had been treated in the past for the thyroid ailment known as Graves' disease.

"The President's and First Lady's prayers are with all of the Bush Family during this time," said White House Press Secretary Sarah Sanders.

Mrs Barbara Bush has long been considered the rock at the center of one of America's most prominent political families, as the wife of a president, the mother of another, George W. Bush, and the mother also of a former Florida governor and onetime presidential aspirant, Jeb Bush.

She first met her husband-to-be at the age of 16; she was a schoolgirl and he was a student at an elite preparatory school in Massachusetts.

They married in 1945 while he was on leave from wartime service as a naval officer. The couple had six children.

As first lady, from 1989 to 1993, she embraced the cause of universal literacy, and founded a foundation for family literacy. She gained a reputation for toughness, wry humor and straight-speaking.

Asked in 2010 about former Alaska Governor Sarah Palin - who sought the vice presidency in 2008 - Mrs. Bush told an interviewer, "I sat next to her once, thought she was beautiful, and I think she's very happy in Alaska, and I hope she'll stay there."but said that she had had a series of recent hospitalisations.