John Edmonds, general secretary of the GMB, condemned as "idiots" those who claimed the labour market needed no regulation and criticised continued opposition among employers to social legislation.
Addressing the conference, he accused bosses of blaming Brussels bureaucrats for social measures such as the minimum wage that they had helped to negotiate.
"Your arguments often look to have as much life as that Monty Python parrot ... European social legislation is a reality and most of the proposals do not come from ... Brussels; they come from agreements between European employers and union organisations," he said.
Mr Edmonds compared the CBI with a father who has disowned his child: "You may not like some of the offspring but they are yours ... and, like it or not, you are one of the parents ... Instead of retreating in various degrees of disarray before each piece of legislation, why don't you try to get ahead of the game?" He urged bosses to abandon opposition to a statutory obligation to train staff. "All over Britain there are employers that neglect to develop the skills of their workforce. There ought to be a law against it."
But Lord Sterling of Plaistow, chairman of P&O, said that for the whole of Europe to have to operate under an inflexible Germanic model was "positively harmful". There had "never been a more misleading title" than the European Social Chapter. "It's not so much a chapter as a loose-leaf ledger."
Every new law involved a cost and waste of management time. Europe was going further down the "path to intrusion" into matters that should be the concern of member-states or individual companies.