Lord and Lady March are "recovering" after being assaulted and tied up in Goodwood House by a burglar who stole £700,000 of treasured family heirlooms.
The 61-year-old and his 54-year-old wife, who were attacked at their stately home on Wednesday morning, described the ordeal as "challenging".
But he said they were "entirely focused" on getting back the stolen goods which have "personal significance" and "historical value".
In a statement, Lord March said: "The last 48 hours have been challenging and I would like to thank Sussex Police, my team here at Goodwood and the local and national press for their support.
"I am pleased to tell you that we are both recovering and entirely focused on providing the police with anything that may help recover the stolen items some of which have such personal significance and others such historical value."