He went into a few more details for WENN, confirming that this was indeed a Harry Palmer project:
"There's a script which I like very much, which is called Cold War Requiem," said Caine, adding that Susan Sarandon was interested in playing his wife in the film.
"It's about an old spy from the '60s in the Cold War, who's now retired - just like me, an old guy. And his enemies come back to kill him because of what he did in those days. ... It's a very good thriller. it might get done, it might not."
"I have a script called Cold War Requiem, which is Harry retired and he's living out his fantasy in some middle class area in London and the guys who he screwed have now got rich and they've decided to come and kill him. I would like to get that done but we haven't got that financed yet.""Harry Palmer" was a name invented for the movie versions of Len Deighton's bestselling novels about an unnamed agent. The novel Spy Story, about the same character, was filmed in 1976 by Lindsay Shonteff featuring a hero called Pat Armstrong (not played by Caine). Caine played a very Palmer-like character named "Harry Anders" in the 1992 HBO film Blue Ice. It's possible that Cold War Requiem might follow the pattern of Blue Ice and slightly change the protagonist's name, but I hope not. The name Harry Palmer carries a lot of weight for spy fans, and I would love to see Caine return to the role once more for a really good final entry, even if it's not based on a Deighton novel. I'd also love to see some of the author's other "Palmer" books like Horse Under Water and An Expensive Place To Die filmed as period pieces set in the Sixties, but that seems less likely and obviously couldn't star Caine.
Caine will next appear in the old guy revenge movie Harry Brown (for which I cannot wait!) and then play a small supporting role in Christopher Nolan's Inception.