Former U.S. President George H.W. Bush, 92, was discharged on Monday from a Houston hospital where he was treated for more than two weeks after developing pneumonia, a spokesman said.

"He is thankful for the many prayers and kind messages he received during his stay, as well as the world-class care that both his doctors and nurses provided," spokesman Jim McGrath said in a statement.

Bush, the country's oldest living ex-president, was released from Houston Methodist Hospital, where he was admitted on Jan. 14 while experiencing shortness of breath.

He had been working with physical therapists to build strength before his release, McGrath said.

Former first lady Barbara Bush, 91, was also admitted to Houston Methodist and treated for bronchitis the same week her husband was hospitalized. She was discharged last week.

The couple marked their 72nd wedding anniversary on Jan. 6.

While in hospital, Bush watched the inauguration of his fellow Republican Donald Trump from his hospital room.

Bush, who was invited to attend the ceremony in Washington but did not endorse Trump in the election, was the only living former president who did not attend the inauguration.

His son George W. Bush, another former president, attended the ceremony.