David Cameron will slap more shackles on trade unions “on day one” of a future Conservative government in a bid to snuff out workers’ right to strike, London Mayor Boris Johnson revealed yesterday.

Members of Tube union RMT woke up to the news on day two of a crippling 48-hour strike over London Underground cuts.

Wealthy Tory Mr Johnson bragged on local radio that the Prime Minister had confirmed “from his lips in public” that one of his first steps if re-elected in 2015 would be draconian new laws that include a clampdown on industrial action in London.

The mayor — himself elected by a mere 16.8 per cent of the city’s voters — said Mr Cameron would grant his wish for a strike ban where less than half of a total workforce turns out to vote for it.

Mr Johnson took to the airwaves to defend Transport for London’s (TfL) refusal to honour a deal with RMT for a station-by-station review of cuts plans that will see every ticket office on the busy network close and 950 jobs lost.

And RMT acting general secretary Mick Cash accused Mr Johnson of engineering this week’s dispute in order to progress his political career.

“The attack on trade unions and public services that has brought London to a standstill has been clearly set up so that Boris Johnson can posture as the hard man of the Tory right,” said Mr Cash.

The mayor had used “Londoners as pawns in his personal crusade for the leadership of the Tory Party.”

But RMT members received a boost yesterday by research from respected pollsters Survation revealing that a mere one in four Londoners believed TfL claims that its “modernisation” plans would improve passengers’ experience.

Half felt the closures would actively damage it.

The results undermined public claims by TfL bosses and Mr Johnson that Londoners have had “quite enough already” and back the mayor’s hard-line stance.

A further 72-hour walkout could start on May 5 if the deal to review its cuts programme is not upheld.

Mr Cash urged TfL bosses and Mr Johnson to see sense and thrash out an agreement at talks planned prior to that deadline.

“The posturing by the mayor and his officials at London Underground and TfL must stop,” said Mr Cash.