The two are running neck-and-neck in the race for leadership of the ruling Conservative Party. It will be down to the wider Conservative membership to select the winner who will take over from Boris Johnson.
"It is going to be a close fought race I would not like to forecast the result. Sunak is more of a traditional Conservative. He will want to hold down taxes and will probably be more cautious in his approach to Foreign Affairs. Truss is what we call a cold war warrior," Balfe said.
The Tory peer described the 42-year-old former finance minister as "more of a consolidator" who would want to win over the middle class and set a conservative course in home affairs, "not opposing change but probably setting a higher bar for its acceptance than Truss."
"Truss sees herself as a new Thatcher except I do not think she is quite as bright. Sunak is more a John Major type figure, rather dull but sound," Balfe said, adding that his bet was with Sunak.
The two candidates are in for six weeks of campaigning and hustings before the final ballot closes on September 2. The result will be announced on September 5.