The 89-year-old told MailOnline that, given the tight security at the property in London's wealthy Kensington, he assumed there was inside involvement.
He said: "I don't have all the facts, but given all the security at the house I'm assuming it was an inside job.
"It's an awful thing to happen just after she had left the house to go to Lapland - although maybe it's better that she wasn't in at the time."
The Metropolitan Police said investigators are keeping an open mind about the raid and that it was being treated as an isolated burglary.
Thieves are believed to have entered through the garden before breaking into safes hidden in the bedroom of the house, which is next to Hyde Park.
All of Ms Ecclestone's jewellery is said to have been taken on Friday night, just after she left the country for her Christmas holiday with her husband Jay Rutland and their daughter Sophia.
Police used sniffer dogs to search the grounds of the property, and are looking through CCTV.
It has been reported that intruders fled with items including rings, earrings and an £80,000 Cartier bangle given to her as a wedding present.
A spokesman for Ms Ecclestone said: "I can sadly confirm there has been a home invasion. Internal security are co-operating with police in this matter.
"Tamara and family are well but obviously angry and shaken by the incident.
"If anyone has information that could help in investigations then please call the police on 101, quoting reference 8786/13DEC19."