A man allegedly shot his elderly wife while she slept as he could no longer afford her medical bills.

William J. Hager confessed to killing his wife Carolyn hours before police arrived at his Florida home on Monday, according to reports.

He is said to have told officers he had been contemplating killing her for several days because she had been in pain.

Hager told police his wife - who had been ill for 15 years - had stated in the past she wanted to die, but had never specifically asked him to kill her.

NBC stationWPTV reported Hager had filed for bankruptcy in 2011 as the couple were struggling with mounting medication bills.

An arrest affidavit stated drank coffee after the killing before calling his daughters.

Hager has been charged with first-degree murder and is being held at St Lucie County Jail.