A UK Government-commissioned review into the employment rights of workers in the so-called “gig economy,” which calls for better jobs to be created, has been denounced as feeble and ineffective.

The review, headed by Matthew Taylor, a former adviser to Tony Blair, recommended a new category of worker called a "dependent contractor" and said there should be "genuine two-way flexibility", giving workers additional protections.

The report by Mr Taylor, the head of the Royal Society of Arts, said low-paid workers should not be "stuck" at the living wage minimum or face insecurity.

Speaking at its launch in London, Theresa May is expected to promise the UK Government will act "to ensure the interests of employees on traditional contracts, the self-employed and those people working in the gig economy are all properly protected".

However, she also will insist that Britain must avoid "overbearing regulation", retain flexibility in the labour market and remain "a home to innovation, new ideas and new business models".

Unions and employment lawyers criticised the report, which has taken nine months to produce, for doing little to help the growing number of workers in delivery and taxi firms such as Deliveroo and Uber.

Frances O'Grady, the TUC general secretary, said: "I worry that many gig economy employers will be breathing a sigh of relief this morning.

"From what we've seen, this review is not the game-changer needed to end insecurity and exploitation at work.

"We'd welcome any nuggets of good news but it doesn't look like the report will shift the balance of power in the modern workplace."

Stephen Cavalier, chief executive of Thompsons Solicitors, said the report's recommendations were "feeble and add another layer of unnecessary complexity", adding: "The creation of a new 'dependent contractor' status for gig economy workers would further complicate existing categories of how workers are defined in law.

"What is needed is one category, which affords all workers all employment rights from day one of their contracts starting. This new status is unclear and unnecessary."

Mr Taylor said the UK's performance on the quantity of work was strong, adding that now was the time to create better jobs.

"The review calls on the Government to adopt the ambition that all work should be fair and decent with scope for fulfilment and development.

"Despite the impact of the National Living Wage and tax credits, there will always be people who are in work but finding it hard to make ends meet. Our social contract with those people should include dignity at work and the realistic scope to progress in the labour market.”

He noted how bad work – “insecure, exploitative, controlling” - was detrimental to people’s health and wellbeing; something which generated cost for vulnerable individuals as well as for wider society.

"Improving the quality of work should be an important part of our productivity strategy," he declared.

Mr Taylor set out seven "principles for fair and decent work", including a goal of "good work for all", additional protections for workers suffering unfair, one-sided flexibility, stronger incentives for firms to treat workers fairly, and a more proactive approach to workplace health.

Mrs May is expected to say that the Taylor review will inform her efforts to ensure that "the high standards of our best employers become the benchmark against which all employers are judged" and that "as the world of work changes, our practices and laws can properly reflect and accommodate those changes".

Len McCluskey, the Unite leader, said the recommendations must be matched by effective enforcement of the law, adding: "Without fully resourced enforcement then all we have from Mr Taylor and the Government is a dog that is all bark and no bite."

Tim Roache, the GMB's general secretary, said: "The recommendations show some laudable aims on the surface - and of course any progress in basic employment rights is welcome - but as a whole it's a disappointing missed opportunity.

"Everyone can pay lip service to wanting good quality, well-paid work but employers could offer that right here and now; they simply choose not to. They won't decide to do so just because they're asked nicely."