NASHVILLE (AP) - Country icon Merle Haggard has canceled his April concert dates as he recovers from a recurring bout of double pneumonia.

"I want to thank my fans for their prayers and well wishes. I hope to be back on the road in May, but I'm taking it one day at a time," the singer said in a statement from his publicist on Tuesday.

The 78-year-old singer of hits like "Okie From Muskogee," ''Mama Tried" and "Workin' Man Blues" had also cancelled dates in February and March. He had a battle with lung cancer in 2008 but still keeps up an ambitious touring schedule.