The 69-year-old Austrian had been suffering from "severe lung disease", Vienna General Hospital said in a statement.

"The transplant was successfully carried out," the statement added.

Lauda won three world drivers' titles in 1975, 1977 and 1984 with Ferrari and McLaren.

He had cut short a holiday in Ibiza last week and returned to Vienna after developing a lung infection, the Osterreich newspaper reported.

Lauda was appointed as Mercedes' non-executive chairman in 2012 and was involved in the signing of Lewis Hamilton to the team.

In 1976, Lauda crashed into an embankment at the Nurburgring circuit in Germany. As flames engulfed his car, Lauda had to be rescued by his fellow drivers but despite suffering horrific burns and being given the last rites, he returned behind the wheel six weeks later.