Frank McCourt, the voluble Irish-American memoirist and retired New York City schoolteacher who wrote Angela's Ashes, is on his deathbed, according to the Belfast Telegraph.

McCourt, who will turn 79 next month, has been battling skin cancer, the Telegraph reports. In May, his brother Malachy McCourt denied reports at the time that Frank was in poor health, describing him as a "hearty fellow" who had been through worse. But the Telegraph says things have gotten worse:

After receiving treatment at the world-famous Memorial Sloan Kettering hospital in New York, the writer was declared well enough to return home to Connecticut.

However, a friend said yesterday that Mr McCourt's condition has deteriorated dramatically since then and that he is seriously ill.

It is understood he became unwell while on a cruise in the Pacific and was transferred to a hospital in Tahiti.

McCourt's three memoirs of his hardscrabble upbringing in Ireland and career as a public schoolteacher in New York—Angela's Ashes, 'Tis, and Teacher Man—were all New York Times bestsellers. He is said to be working on his first novel.