David Cameron will present plans for an EU referendum and Scottish devolution in his first Conservative Queen’s speech but is expected to delay controversial proposals to abolish the Human Rights Act.

The prime minister was facing criticism from some of his backbenchers, many in the judiciary, as well as Labour, the SNP and his former deputy prime minister, Nick Clegg, over the Tory manifesto pledge to replace human rights laws with a British bill of rights.

It is now expected to be announced as a consultation rather than a draft law, as Cameron may not have the support to get it through the Commons with his wafer-thin majority of 12.

Alex Salmond, the SNP MP and former first minister of Scotland, told the BBC it showed the government was in “headlong retreat” and that it “had not taken long to get blown off course”.

But without commenting on the timing, Liz Truss, the Conservative environment secretary, insisted the plan was “absolutely” going be delivered at some point because it was a “clear manifesto pledge”.

The centrepiece of the Queen’s speech will be Cameron’s law promising a referendum on Britain’s EU membership before the end of 2017, which was blocked by the Lib Dems in the coalition government. The wording of the question has not been finalised but the “yes” option is likely to be to stay part of the EU.

Other key legislation includes:

A five-year lock on tax rises including VAT, income tax and national insurance

No income tax for those working 30 hours a week on the minimum wage

The extension of right to buy to housing association tenants

Further Scottish devolution and measures that will give English MPs more say over laws that only affect England

A counter-extremism bill to tackle radicalisation

A blanket ban on so-called legal highs

An increase in free childcare for three- and four-year-olds to 30 hours a week

Reform of strike laws to require a higher turnout of union members

Cameron said his legislative programme would mean “wherever you live, you can have the chance of a good education, a decent job, a home of your own and the peace of mind that comes from being able to raise a family and enjoy a secure retirement”.

However, it is the omission of any proposed legislation to scrap the current human rights laws that will be the biggest surprise. The proposals will be on hold until Michael Gove, the justice secretary, has conducted a wider consultation.

Although the government has an overall majority of 12 seats in the Commons, Cameron is massively outnumbered in the House of Lords, and his whips will have to be alert to any signs of rebellions by backbench MPs, possibly made restive by the prime minister’s promotion of an insufficiently ambitious EU renegotiation agenda.

Ministers acknowledge that a conflict over the Human Rights Act may prove to be one of the most difficult politically, legally and intellectually for the Tories.

In an attempt to rally his demoralised party, Clegg was due to attack Cameron for his approach to human rights in the Commons after the Queen’s speech. “The Liberal Democrats worked hard to ensure the coalition government’s agenda had a clear thread of liberalism running through it – from the priority we gave to mental health and the green agenda, to creating the pupil premium and protecting our civil liberties,” he said.

“So it is dispiriting – if pretty unsurprising – to see how quickly, instead of building on those achievements, the new Conservative government is turning its back on that liberal stance. The human rights we hold dear, our right to privacy in an online age, our future as an open-minded, outward-looking country, are all hanging in the balance again because of the measures being announced by the Conservative government.”

Andy Burnham, the shadow health secretary, had signalled his determination to make the Human Rights Act a central part of Labour opposition to the Queen’s speech if he was successful in his bid for the party leadership. He said he hoped Labour “throws the kitchen sink” at opposing the measures.