Radical leftist Jeremy Corbyn attacked government plans to curb strike action on his first day in parliament on Monday, after becoming leader of Britain's Labour opposition despite internal dissent.
Corbyn, 66, who swept to victory on Saturday, set the scene for a heated debate over the Trade Union Bill by saying even some Conservatives saw parts of it as "something from a fascist dictatorship".
Corbyn's stunning success over the weekend was boosted by support from many of Labour's 15 affiliated trade unions, including the country's two largest -- Unite and Unison.
Former Conservative party chairman David Davis on Sunday criticised the proposed law's requirement for picketers to give their names to the police.
"What is this? This isn't Franco's Britain, this is Queen Elizabeth II's Britain," he said.
The legislation would impose a minimum 50-percent turnout in strike ballots. Currently, strikes can be called if the majority of those taking part in a ballot vote in favour.
It would also double the amount of notice unions have to give before staging a strike, allow employers to use agency workers to replace striking staff and introduce fines if picketers do not wear an official armband.
Former union official Corbyn said Monday that Britain "already has the most restrictive trade union laws in western Europe".
Corbyn's new cabinet has come under the microscope, and it was one of his new recruits -- shadow business secretary Angela Eagle -- who led Labour's opposition to the bill in Monday's debate.
She called the legislation "a partisan...draconian and sinister attack" on unions that "saddens me beyond words".
Unite leader Len McCluskey condemned the proposed changes and called Corbyn's victory "a blissful dawn" for politics in Britain.
The far-left MP of over 30 years shocked the experts after winning the support of almost 60 percent of party members and supporters.
As one of his first acts, Corbyn vowed to challenge the Conservatives' claim to be the party of "hardworking people".
"Today and tomorrow in the House of Parliament they will demonstrate that claim to be false," he wrote in Monday's Daily Mirror.
"The Tories are hitting working people with a double whammy -- attacking the trade unions that defend jobs and win pay rises, and attacking the tax credits that provide a safety net for the millions of people stuck in low-paid jobs," he added.
Corbyn's selection has ruffled moderates within the party, beginning with the announcement of his shadow cabinet on Sunday.
His selection of left-wing supporter John McDonnell for the key role of shadow chancellor made a "nonsense" of his pledge to reach out to all factions, said former Labour interior minister Charles Clarke, an ally of former leader Tony Blair -- scourge of the party's far left .
"He had choices of who he was going to appoint and the choice he made was to go down the most hard-line position," he told BBC Radio 4's Today programme.
"Labour MPs will start working themselves without the involvement of John McDonnell to develop economic policy. If John continues to express the views he holds very deeply, people will start to put forward their own alternatives," he added.
McDonnell has previously joked about "assassinating" former Tory prime minister Margaret Thatcher, called for the honouring of IRA members and advocated nationalising the banking, energy and rail sectors.
Corbyn also defended the lack of women in the shadow cabinet's traditional top roles, saying it was "an 18th century" attitude to view the foreign and finance ministries as more important than the health and education departments.
In total, women will fill 16 of the 31 posts in Corbyn's senior team.