Pele has been treated in a hospital for "severe exhaustion" after collapsing in his native Brazil.
According to Reuters (h/t the Daily Mail), the Football Writers' Association broke the news in a statement:
"In the early hours of Thursday morning, Pele collapsed and was taken to hospital in Brazil where he has undergone a series of tests which appear to point to severe exhaustion.
"He remains on fluids while doctors monitor his recovery. Thankfully, there is no suggestion of anything more serious than exhaustion."
The FWA was to hold a dinner in the football legend's honour on Sunday at the Savoy hotel in London, but his visit to the English capital has now been cancelled.
The 77-year-old used a wheelchair at the draw for the 2018 World Cup in Russia in December, which was his last major public appearance.
He has spent time in hospital because of kidney and prostate issues, while he also underwent corrective surgery in 2016 to repair the hip replacement he received in 2012.
Pele scored 1,281 goals over the course of his career between 1956 and 1977, spending the majority of his time at Santos before joining New York Cosmos in 1975.
His goalscoring feats include 77 goals for Brazil's national team in 91 appearances, cementing his place as one of the greatest players of all time.
Pele also won the World Cup with the Selecao in 1958, 1962 and 1970, and he remains the only player to win football's greatest prize on three occasions.