Pinter, 75, has been battling cancer and doctors had already barred him from attending Wednesday's Nobel Prize ceremony in Sweden, the BBC noted.
"He hasn't been very well for a while. He is back in hospital," Pinter's agent, Judy Daish, told the BBC.
Pinter recorded his laureate's lecture Sunday to be screened during the Nobel ceremony, Daish said.
Daish refused to reveal the nature of Pinter's latest medical setback.
The author of plays such as "The Birthday Party" and "Betrayal" was named a $1.3 million Nobel Prize winner in October.
Puzzle-maker slips 'Murdoch Is Evil' into Rupert Murdoch's Sunday Telegraph
Workers accuse National Zoo of animal mismanagement