George Osborne has said William Hauge was "unprincipled" when the foreign secretary was leader of the Conservative Party between 1997 and 2001.
Speaking to BBC Radio 4's Today programme this morning, the chancellor attacked the Labour Party for joining with Tory rebels to defeat the government over the EU Budget negotiations.
Osborne said Labour's " opportunistic" tactics reminded him of the dark days of opposition after the 1997 Labour landslide.
"Labour took a step further away from government last night because they took such an opportunistic position," he said.
"It reminded me of the early part of the Conservative Party's period in opposition when we took opportunistic positions and unprincipled positions in parliament that actually pushed us further away from being an alternative government."
The leader of the Conservatives at the time was of course, William Hague - now Osborne's senior cabinet colleague.
Intriguingly between 1997 and 2001 Osborne served as Hague's speechwriter and political secretary, helping Hague prepare for his prime minister's questions battles with Tony Blair.