Ryan O'Neal says he plans to marry Farrah Fawcett, who is struggling to overcome cancer.

The 68-year-old actor says in an interview with ABC television that he asked his longtime companion to marry him and "she's agreed".

O'Neal says they will wed "as soon as she can say yes".

The ABC interview with O'Neal airs this Friday.

Fawcett was diagnosed in 2006 with anal cancer that has spread to her liver.

The 'Charlie's Angels' star and O'Neal, who was nominated for an Oscar for his role in 'Love Story', have a 24-year-old son, Redmond.

O'Neal says the 62-year-old actress is "fighting for her life", but despite her declining health, they will "absolutely" get married.