The Liberal Democrats have taken a personal swipe at Lord Mandelson, after the former Labour business secretary urged Labour and the government today to think again about the controversial HS2 rail link.
Writing in the Financial Times today, the powerful Labour peer said the project could prove "an expensive mistake" and "damaging" to the northern regions it is intended to help.
And he admitted that Labour's decision to back the scheme enthusiastically in the run-up to the 2010 general election was "partly politically-driven" and did not give sufficient consideration to alternatives.
The u-turn prompted a fierce rebuke from Lib Dem transport minister Norman Baker, who said "unlike Peter Mandelson we can't all hop on a private jet".
"Thankfully, since Blair and Brown are gone the country no longer has to do whatever Peter Mandelson says. And given the fiasco of the Millennium Dome, for which he had personal responsibility, I hardly think he is the best person to offer advice on large projects anyway," he said.
"The Liberal Democrats were the first party to champion high speed rail, the Conservatives got on board and it was Labour's Andrew Adonis who got it started. There is a genuine cross-party consensus. It will create hundreds of thousands of jobs; be a major boost to our economy, especially in the North of England; and will help us shift to the clean, green economy of the future."
Labour peer Lord Adonis, a vocal backer of HS2, took to Twitter to highlight the "strong continuing support" for the scheme that the party's shadow transport secretary Maria Eagle voiced in the Commons as recently as last week."
Lord Adonis, who was Transport Secretary at the time the Brown government gave its backing to the scheme, added: "Incoming Labour govt in 1974 scrapped Channel Tunnel and Maplin airport, with both under construction. We won't make same mistake on HS2."