Merle Haggard performs onstage during day one of 2015 Stagecoach, California's Country Music Festival, at The Empire Polo Club on April 24, 2015 in Indio, California.

Country icon Merle Haggard is in a California hospital for treatment of a recurring bout of double pneumonia.

A statement from his publicist on Tuesday said Haggard has had to postpone his concert dates in March.

Merle Haggard Returns to the Stage Ahead of Schedule

The 78-year-old singer had also canceled some dates in February because he was still feeling weak from a previous case of pneumonia in both lungs, but then returned to the stage last month.

The statement said that his doctors wanted him to take one more month off the road to rest and recover.