A 1921 oil painting by former British Prime Minister Winston Churchill is set to be sold at Phillips Auction house on June 23 and estimates for the long-thought-lost painting are said to be over $2 million, according to the Robb Report.

The painting, “The Moat, Breccles,” was originally gifted to Greek shipping magnate and Jackie Kennedy’s second husband, Aristotle Onassis, and used to hang on his yacht, The Christina.  It is being sold by Onassis’ heirs, presumably his granddaughter Athina Onassis.

The market for Churchill paintings has heated up recently and, according to the Robb Report. At Christie’s in March, one buyer snatched up a trio of his paintings for about $16 million. Another Churchill painting that was owned by Angelina Jolie sold for $11.5 million at the same auction.

To promote this month’s sale, Phillips will display the painting at the company’s Park Avenue headquarters from June 15 alongside a replica of Onassis’s yacht bar, which was frequented by high society guests such as John D. Rockefeller, Eva Perén, Richard Burton, Elizabeth Taylor and Marilyn Monroe.