Separately, his wife Barbara Bush has also been hospitalised as a precaution
George HW Bush has been admitted to intensive care, a spokesperson for the former US president has confirmed.
In a statement, Jim McGrath said the 92-year-old had been admitted to the intensive care unit in the Houston Methodist Hospital to address an "acute respiratory problem stemming from pneumonia".
The former president was sedated for a procedure to 'protect and clear' his airway.
He is said to be stable and resting comfortably.
Meanwhile, his wife Barbara Bush has also been admitted to hospital as a precaution after 'experiencing fatigue and coughing'.
George HW Bush Bush served as the 41st US President from 1989 to 1993, and is the father of the 43rd President George W Bush.
It was reported today that neither he or his wife would be attending the inauguration of President-elect Donald Trump this week.