He told the conference that this summer's stoppages on the railways and London Underground and at the Post Office had convinced him to act on a long-standing but unfulfilled Tory aim.
The strikes were "completely unacceptable" and his plans would allow unions to be sued for damages if they organised stoppages that were "disproportionately damaging to the public". Sources close to Mr Lang said the legislation would not necessarily be restricted to publicly owned services.
The need to take reforms of union law "one step further" was justified by comparing this summer's strikes to the Winter of Discontent. They were a "reprise, like a bad dream, of those old, ugly attitudes".
Those attitudes had been eradicated in most industries by Tory legislation. "It's in the few remaining monopolies, in the public sector and providing public services, that the virus survives," Mr Lang said.
He promised to publish a "package of new proposals" when the Commons returns next week but gave no details of how the plan would work in practice or when it might become law. It is possible it might form part of the Tories' general election manifesto.
In interviews before and after his speech Mr Lang said the plans would apply to public services which had a monopoly, but that would not necessarily include railway services where there was, for example, an alternative bus service.
His senior advisers said the Government might allow civil courts to decide whether any industrial action was "disproportionately damaging". Ministers, however, could issue a code of practice to guide courts of law. The intention was not to make industrial action impossible, but to limit its impact. Any union leading a strike which caused the complete withdrawal of a monopoly service could be liable to legal action by the employer, or by customers.
Mr Lang's proposals could serve to minimise any splits within the Labour Party. Unions tempted publicly to criticise Tony Blair in the run-up to the election will keep their own counsel when they contemplate the alternative.
The plans, however, may also mean that Labour's present review of industrial action in the public services could also yield tough proposals to compete with the Conservatives.
Mr Lang's plans were attacked by David Blunkett, Labour's education and employment spokesman, as neither new nor workable. Mr Blunkett irritated unions at the TUC last month with pre-emptive proposals for more use of binding arbitration and for forcing new offers to be put to ballots of union members. The TUC and unions said the plans, if effective, would leave public-sector workers "defenceless".
Rodney Bickerstaffe, general secretary of Unison, the country's largest union, said the best way of averting industrial action was to treat workers decently, pay a proper wage and ensure services were properly funded.Reuse content